Reference · 374 dash numbers · 349 of them AS568B standard sizes

AS568 O-ring size chart

Every dash number in SAE AS568B (aerospace size standard for O-rings), with inside diameter, cross section and outside diameter in inches and millimetres and the published tolerance on each. Every row has its own anchor: search the page for a dash number such as AS568-214 to jump to it.

How to read a dash number

A dash number is not a diameter. The series it sits in fixes the cross section - the thickness of the cord - and the position within the series sets the inside diameter. So every 2xx size shares one cross section and differs only in bore, which is why a seal that leaks is so often the right inside diameter in the wrong series. The fractional names are nicknames rather than dimensions: the 1xx cord is called 3/32 and measures 0.103 inches.

Outside diameter is a sum, not a published figure

Outside diameter is not a published AS568 dimension. The standard fixes the inside diameter and the cross section, and the outside diameter follows from them: OD = ID + 2 x CS. Every outside diameter on this site is that sum, not a figure read from a table, and it inherits both tolerances rather than carrying one of its own.

What is here, and what is not

This chart carries the five cross-section series - 0xx, 1xx, 2xx, 3xx and 4xx. It does NOT carry the 900 series, the 20 straight-thread boss gaskets AS568 also lists: those are boss seals rather than O-rings in the usual sense and are sized to the fitting, so they are left out rather than mixed in. Dash numbers -400 to -424 are carried and flagged: two of the four catalogues list them under AS568, and the AS568B list of 369 standard sizes does not.

Of the 374 dash numbers listed, 349 are AS568B standard sizes and 25 are the catalogued -400 to -424 block, marked as such on every page they appear. Every dimension was read from at least two independent published tables before it was printed.

50 sizes · cross section 0.070" (1.78 mm) ±0.003"

0xx series

Pneumatic, instrumentation and small seals. Standard dash numbers 004 to 050. -001, -002, -003 carry a smaller cross section than the rest of the series.

AS568 0xx series dash numbers with inside diameter, cross section and outside diameter, each with its published tolerance.
Dash	ID (in)	CS (in)	OD (in)	ID (mm)	CS (mm)	OD (mm)	AS568B	Sources
AS568-001	0.029 ±0.004	0.040 ±0.003	0.109	0.74 ±0.10	1.02 ±0.08	2.78	yes	5
AS568-002	0.042 ±0.004	0.050 ±0.003	0.142	1.07 ±0.10	1.27 ±0.08	3.61	yes	5
AS568-003	0.056 ±0.004	0.060 ±0.003	0.176	1.42 ±0.10	1.52 ±0.08	4.46	yes	5
AS568-004	0.070 ±0.005	0.070 ±0.003	0.210	1.78 ±0.13	1.78 ±0.08	5.34	yes	6
AS568-005	0.101 ±0.005	0.070 ±0.003	0.241	2.57 ±0.13	1.78 ±0.08	6.13	yes	6
AS568-006	0.114 ±0.005	0.070 ±0.003	0.254	2.90 ±0.13	1.78 ±0.08	6.46	yes	6
AS568-007	0.145 ±0.005	0.070 ±0.003	0.285	3.68 ±0.13	1.78 ±0.08	7.24	yes	6
AS568-008	0.176 ±0.005	0.070 ±0.003	0.316	4.47 ±0.13	1.78 ±0.08	8.03	yes	6
AS568-009	0.208 ±0.005	0.070 ±0.003	0.348	5.28 ±0.13	1.78 ±0.08	8.84	yes	5
AS568-010	0.239 ±0.005	0.070 ±0.003	0.379	6.07 ±0.13	1.78 ±0.08	9.63	yes	5
AS568-011	0.301 ±0.005	0.070 ±0.003	0.441	7.65 ±0.13	1.78 ±0.08	11.21	yes	5
AS568-012	0.364 ±0.005	0.070 ±0.003	0.504	9.25 ±0.13	1.78 ±0.08	12.81	yes	5
AS568-013	0.426 ±0.005	0.070 ±0.003	0.566	10.82 ±0.13	1.78 ±0.08	14.38	yes	5
AS568-014	0.489 ±0.005	0.070 ±0.003	0.629	12.42 ±0.13	1.78 ±0.08	15.98	yes	5
AS568-015	0.551 ±0.007	0.070 ±0.003	0.691	14.00 ±0.18	1.78 ±0.08	17.56	yes	5
AS568-016	0.614 ±0.009	0.070 ±0.003	0.754	15.60 ±0.23	1.78 ±0.08	19.16	yes	5
AS568-017	0.676 ±0.009	0.070 ±0.003	0.816	17.17 ±0.23	1.78 ±0.08	20.73	yes	5
AS568-018	0.739 ±0.009	0.070 ±0.003	0.879	18.77 ±0.23	1.78 ±0.08	22.33	yes	5
AS568-019	0.801 ±0.009	0.070 ±0.003	0.941	20.35 ±0.23	1.78 ±0.08	23.91	yes	5
AS568-020	0.864 ±0.009	0.070 ±0.003	1.004	21.95 ±0.23	1.78 ±0.08	25.51	yes	5
AS568-021	0.926 ±0.009	0.070 ±0.003	1.066	23.52 ±0.23	1.78 ±0.08	27.08	yes	5
AS568-022	0.989 ±0.010	0.070 ±0.003	1.129	25.12 ±0.25	1.78 ±0.08	28.68	yes	5
AS568-023	1.051 ±0.010	0.070 ±0.003	1.191	26.70 ±0.25	1.78 ±0.08	30.26	yes	5
AS568-024	1.114 ±0.010	0.070 ±0.003	1.254	28.30 ±0.25	1.78 ±0.08	31.86	yes	5
AS568-025	1.176 ±0.011	0.070 ±0.003	1.316	29.87 ±0.28	1.78 ±0.08	33.43	yes	5
AS568-026	1.239 ±0.011	0.070 ±0.003	1.379	31.47 ±0.28	1.78 ±0.08	35.03	yes	5
AS568-027	1.301 ±0.011	0.070 ±0.003	1.441	33.05 ±0.28	1.78 ±0.08	36.61	yes	5
AS568-028	1.364 ±0.013	0.070 ±0.003	1.504	34.65 ±0.33	1.78 ±0.08	38.21	yes	5
AS568-029	1.489 ±0.013	0.070 ±0.003	1.629	37.82 ±0.33	1.78 ±0.08	41.38	yes	5
AS568-030	1.614 ±0.013	0.070 ±0.003	1.754	41.00 ±0.33	1.78 ±0.08	44.56	yes	5
AS568-031	1.739 ±0.015	0.070 ±0.003	1.879	44.17 ±0.38	1.78 ±0.08	47.73	yes	5
AS568-032	1.864 ±0.015	0.070 ±0.003	2.004	47.35 ±0.38	1.78 ±0.08	50.91	yes	5
AS568-033	1.989 ±0.018	0.070 ±0.003	2.129	50.52 ±0.46	1.78 ±0.08	54.08	yes	5
AS568-034	2.114 ±0.018	0.070 ±0.003	2.254	53.70 ±0.46	1.78 ±0.08	57.26	yes	5
AS568-035	2.239 ±0.018	0.070 ±0.003	2.379	56.87 ±0.46	1.78 ±0.08	60.43	yes	5
AS568-036	2.364 ±0.018	0.070 ±0.003	2.504	60.05 ±0.46	1.78 ±0.08	63.61	yes	5
AS568-037	2.489 ±0.018	0.070 ±0.003	2.629	63.22 ±0.46	1.78 ±0.08	66.78	yes	5
AS568-038	2.614 ±0.020	0.070 ±0.003	2.754	66.40 ±0.51	1.78 ±0.08	69.96	yes	5
AS568-039	2.739 ±0.020	0.070 ±0.003	2.879	69.57 ±0.51	1.78 ±0.08	73.13	yes	5
AS568-040	2.864 ±0.020	0.070 ±0.003	3.004	72.75 ±0.51	1.78 ±0.08	76.31	yes	5
AS568-041	2.989 ±0.024	0.070 ±0.003	3.129	75.92 ±0.61	1.78 ±0.08	79.48	yes	5
AS568-042	3.239 ±0.024	0.070 ±0.003	3.379	82.27 ±0.61	1.78 ±0.08	85.83	yes	5
AS568-043	3.489 ±0.024	0.070 ±0.003	3.629	88.62 ±0.61	1.78 ±0.08	92.18	yes	5
AS568-044	3.739 ±0.027	0.070 ±0.003	3.879	94.97 ±0.69	1.78 ±0.08	98.53	yes	5
AS568-045	3.989 ±0.027	0.070 ±0.003	4.129	101.32 ±0.69	1.78 ±0.08	104.88	yes	5
AS568-046	4.239 ±0.030	0.070 ±0.003	4.379	107.67 ±0.76	1.78 ±0.08	111.23	yes	5
AS568-047	4.489 ±0.030	0.070 ±0.003	4.629	114.02 ±0.76	1.78 ±0.08	117.58	yes	5
AS568-048	4.739 ±0.030	0.070 ±0.003	4.879	120.37 ±0.76	1.78 ±0.08	123.93	yes	5
AS568-049	4.989 ±0.037	0.070 ±0.003	5.129	126.72 ±0.94	1.78 ±0.08	130.28	yes	5
AS568-050	5.239 ±0.037	0.070 ±0.003	5.379	133.07 ±0.94	1.78 ±0.08	136.63	yes	5

77 sizes · cross section 0.103" (2.62 mm) ±0.003"

1xx series

Hydraulic, pump and valve. Standard dash numbers 102 to 178.

AS568 1xx series dash numbers with inside diameter, cross section and outside diameter, each with its published tolerance.
Dash	ID (in)	CS (in)	OD (in)	ID (mm)	CS (mm)	OD (mm)	AS568B	Sources
AS568-102	0.049 ±0.005	0.103 ±0.003	0.255	1.24 ±0.13	2.62 ±0.08	6.48	yes	5
AS568-103	0.081 ±0.005	0.103 ±0.003	0.287	2.06 ±0.13	2.62 ±0.08	7.30	yes	5
AS568-104	0.112 ±0.005	0.103 ±0.003	0.318	2.84 ±0.13	2.62 ±0.08	8.08	yes	5
AS568-105	0.143 ±0.005	0.103 ±0.003	0.349	3.63 ±0.13	2.62 ±0.08	8.87	yes	5
AS568-106	0.174 ±0.005	0.103 ±0.003	0.380	4.42 ±0.13	2.62 ±0.08	9.66	yes	5
AS568-107	0.206 ±0.005	0.103 ±0.003	0.412	5.23 ±0.13	2.62 ±0.08	10.47	yes	5
AS568-108	0.237 ±0.005	0.103 ±0.003	0.443	6.02 ±0.13	2.62 ±0.08	11.26	yes	5
AS568-109	0.299 ±0.005	0.103 ±0.003	0.505	7.59 ±0.13	2.62 ±0.08	12.83	yes	5
AS568-110	0.362 ±0.005	0.103 ±0.003	0.568	9.19 ±0.13	2.62 ±0.08	14.43	yes	5
AS568-111	0.424 ±0.005	0.103 ±0.003	0.630	10.77 ±0.13	2.62 ±0.08	16.01	yes	5
AS568-112	0.487 ±0.005	0.103 ±0.003	0.693	12.37 ±0.13	2.62 ±0.08	17.61	yes	5
AS568-113	0.549 ±0.007	0.103 ±0.003	0.755	13.94 ±0.18	2.62 ±0.08	19.18	yes	5
AS568-114	0.612 ±0.009	0.103 ±0.003	0.818	15.54 ±0.23	2.62 ±0.08	20.78	yes	5
AS568-115	0.674 ±0.009	0.103 ±0.003	0.880	17.12 ±0.23	2.62 ±0.08	22.36	yes	5
AS568-116	0.737 ±0.009	0.103 ±0.003	0.943	18.72 ±0.23	2.62 ±0.08	23.96	yes	5
AS568-117	0.799 ±0.010	0.103 ±0.003	1.005	20.29 ±0.25	2.62 ±0.08	25.53	yes	5
AS568-118	0.862 ±0.010	0.103 ±0.003	1.068	21.89 ±0.25	2.62 ±0.08	27.13	yes	5
AS568-119	0.924 ±0.010	0.103 ±0.003	1.130	23.47 ±0.25	2.62 ±0.08	28.71	yes	5
AS568-120	0.987 ±0.010	0.103 ±0.003	1.193	25.07 ±0.25	2.62 ±0.08	30.31	yes	5
AS568-121	1.049 ±0.010	0.103 ±0.003	1.255	26.64 ±0.25	2.62 ±0.08	31.88	yes	5
AS568-122	1.112 ±0.010	0.103 ±0.003	1.318	28.24 ±0.25	2.62 ±0.08	33.48	yes	5
AS568-123	1.174 ±0.012	0.103 ±0.003	1.380	29.82 ±0.30	2.62 ±0.08	35.06	yes	5
AS568-124	1.237 ±0.012	0.103 ±0.003	1.443	31.42 ±0.30	2.62 ±0.08	36.66	yes	5
AS568-125	1.299 ±0.012	0.103 ±0.003	1.505	32.99 ±0.30	2.62 ±0.08	38.23	yes	5
AS568-126	1.362 ±0.012	0.103 ±0.003	1.568	34.59 ±0.30	2.62 ±0.08	39.83	yes	5
AS568-127	1.424 ±0.012	0.103 ±0.003	1.630	36.17 ±0.30	2.62 ±0.08	41.41	yes	5
AS568-128	1.487 ±0.012	0.103 ±0.003	1.693	37.77 ±0.30	2.62 ±0.08	43.01	yes	5
AS568-129	1.549 ±0.015	0.103 ±0.003	1.755	39.34 ±0.38	2.62 ±0.08	44.58	yes	5
AS568-130	1.612 ±0.015	0.103 ±0.003	1.818	40.94 ±0.38	2.62 ±0.08	46.18	yes	5
AS568-131	1.674 ±0.015	0.103 ±0.003	1.880	42.52 ±0.38	2.62 ±0.08	47.76	yes	5
AS568-132	1.737 ±0.015	0.103 ±0.003	1.943	44.12 ±0.38	2.62 ±0.08	49.36	yes	5
AS568-133	1.799 ±0.015	0.103 ±0.003	2.005	45.69 ±0.38	2.62 ±0.08	50.93	yes	5
AS568-134	1.862 ±0.015	0.103 ±0.003	2.068	47.29 ±0.38	2.62 ±0.08	52.53	yes	5
AS568-135	1.925 ±0.017	0.103 ±0.003	2.131	48.90 ±0.43	2.62 ±0.08	54.14	yes	5
AS568-136	1.987 ±0.017	0.103 ±0.003	2.193	50.47 ±0.43	2.62 ±0.08	55.71	yes	5
AS568-137	2.050 ±0.017	0.103 ±0.003	2.256	52.07 ±0.43	2.62 ±0.08	57.31	yes	5
AS568-138	2.112 ±0.017	0.103 ±0.003	2.318	53.64 ±0.43	2.62 ±0.08	58.88	yes	5
AS568-139	2.175 ±0.017	0.103 ±0.003	2.381	55.25 ±0.43	2.62 ±0.08	60.49	yes	5
AS568-140	2.237 ±0.017	0.103 ±0.003	2.443	56.82 ±0.43	2.62 ±0.08	62.06	yes	5
AS568-141	2.300 ±0.020	0.103 ±0.003	2.506	58.42 ±0.51	2.62 ±0.08	63.66	yes	5
AS568-142	2.362 ±0.020	0.103 ±0.003	2.568	59.99 ±0.51	2.62 ±0.08	65.23	yes	5
AS568-143	2.425 ±0.020	0.103 ±0.003	2.631	61.60 ±0.51	2.62 ±0.08	66.84	yes	5
AS568-144	2.487 ±0.020	0.103 ±0.003	2.693	63.17 ±0.51	2.62 ±0.08	68.41	yes	5
AS568-145	2.550 ±0.020	0.103 ±0.003	2.756	64.77 ±0.51	2.62 ±0.08	70.01	yes	5
AS568-146	2.612 ±0.020	0.103 ±0.003	2.818	66.34 ±0.51	2.62 ±0.08	71.58	yes	5
AS568-147	2.675 ±0.022	0.103 ±0.003	2.881	67.95 ±0.56	2.62 ±0.08	73.19	yes	5
AS568-148	2.737 ±0.022	0.103 ±0.003	2.943	69.52 ±0.56	2.62 ±0.08	74.76	yes	5
AS568-149	2.800 ±0.022	0.103 ±0.003	3.006	71.12 ±0.56	2.62 ±0.08	76.36	yes	5
AS568-150	2.862 ±0.022	0.103 ±0.003	3.068	72.69 ±0.56	2.62 ±0.08	77.93	yes	5
AS568-151	2.987 ±0.024	0.103 ±0.003	3.193	75.87 ±0.61	2.62 ±0.08	81.11	yes	5
AS568-152	3.237 ±0.024	0.103 ±0.003	3.443	82.22 ±0.61	2.62 ±0.08	87.46	yes	5
AS568-153	3.487 ±0.024	0.103 ±0.003	3.693	88.57 ±0.61	2.62 ±0.08	93.81	yes	5
AS568-154	3.737 ±0.028	0.103 ±0.003	3.943	94.92 ±0.71	2.62 ±0.08	100.16	yes	5
AS568-155	3.987 ±0.028	0.103 ±0.003	4.193	101.27 ±0.71	2.62 ±0.08	106.51	yes	5
AS568-156	4.237 ±0.030	0.103 ±0.003	4.443	107.62 ±0.76	2.62 ±0.08	112.86	yes	5
AS568-157	4.487 ±0.030	0.103 ±0.003	4.693	113.97 ±0.76	2.62 ±0.08	119.21	yes	5
AS568-158	4.737 ±0.030	0.103 ±0.003	4.943	120.32 ±0.76	2.62 ±0.08	125.56	yes	5
AS568-159	4.987 ±0.035	0.103 ±0.003	5.193	126.67 ±0.89	2.62 ±0.08	131.91	yes	5
AS568-160	5.237 ±0.035	0.103 ±0.003	5.443	133.02 ±0.89	2.62 ±0.08	138.26	yes	5
AS568-161	5.487 ±0.035	0.103 ±0.003	5.693	139.37 ±0.89	2.62 ±0.08	144.61	yes	5
AS568-162	5.737 ±0.035	0.103 ±0.003	5.943	145.72 ±0.89	2.62 ±0.08	150.96	yes	5
AS568-163	5.987 ±0.035	0.103 ±0.003	6.193	152.07 ±0.89	2.62 ±0.08	157.31	yes	5
AS568-164	6.237 ±0.040	0.103 ±0.003	6.443	158.42 ±1.02	2.62 ±0.08	163.66	yes	5
AS568-165	6.487 ±0.040	0.103 ±0.003	6.693	164.77 ±1.02	2.62 ±0.08	170.01	yes	5
AS568-166	6.737 ±0.040	0.103 ±0.003	6.943	171.12 ±1.02	2.62 ±0.08	176.36	yes	5
AS568-167	6.987 ±0.040	0.103 ±0.003	7.193	177.47 ±1.02	2.62 ±0.08	182.71	yes	5
AS568-168	7.237 ±0.045	0.103 ±0.003	7.443	183.82 ±1.14	2.62 ±0.08	189.06	yes	5
AS568-169	7.487 ±0.045	0.103 ±0.003	7.693	190.17 ±1.14	2.62 ±0.08	195.41	yes	5
AS568-170	7.737 ±0.045	0.103 ±0.003	7.943	196.52 ±1.14	2.62 ±0.08	201.76	yes	5
AS568-171	7.987 ±0.045	0.103 ±0.003	8.193	202.87 ±1.14	2.62 ±0.08	208.11	yes	5
AS568-172	8.237 ±0.050	0.103 ±0.003	8.443	209.22 ±1.27	2.62 ±0.08	214.46	yes	5
AS568-173	8.487 ±0.050	0.103 ±0.003	8.693	215.57 ±1.27	2.62 ±0.08	220.81	yes	5
AS568-174	8.737 ±0.050	0.103 ±0.003	8.943	221.92 ±1.27	2.62 ±0.08	227.16	yes	5
AS568-175	8.987 ±0.050	0.103 ±0.003	9.193	228.27 ±1.27	2.62 ±0.08	233.51	yes	5
AS568-176	9.237 ±0.055	0.103 ±0.003	9.443	234.62 ±1.40	2.62 ±0.08	239.86	yes	5
AS568-177	9.487 ±0.055	0.103 ±0.003	9.693	240.97 ±1.40	2.62 ±0.08	246.21	yes	5
AS568-178	9.737 ±0.055	0.103 ±0.003	9.943	247.32 ±1.40	2.62 ±0.08	252.56	yes	5

Where the sources disagree in the 1xx series

AS568-107: Published inside diameters differ: 0.206 in (as568-arc), 0.205 in (as568-oringseal), 0.206 in (as568-parco), 0.206 in (as568-savvy). The figure printed is 0.206 in, carried by 3 of the 4 sources.

84 sizes · cross section 0.139" (3.53 mm) ±0.004"

2xx series

General purpose and cylinders. Standard dash numbers 201 to 284.

AS568 2xx series dash numbers with inside diameter, cross section and outside diameter, each with its published tolerance.
Dash	ID (in)	CS (in)	OD (in)	ID (mm)	CS (mm)	OD (mm)	AS568B	Sources
AS568-201	0.171 ±0.005	0.139 ±0.004	0.449	4.34 ±0.13	3.53 ±0.10	11.40	yes	5
AS568-202	0.234 ±0.005	0.139 ±0.004	0.512	5.94 ±0.13	3.53 ±0.10	13.00	yes	5
AS568-203	0.296 ±0.005	0.139 ±0.004	0.574	7.52 ±0.13	3.53 ±0.10	14.58	yes	5
AS568-204	0.359 ±0.005	0.139 ±0.004	0.637	9.12 ±0.13	3.53 ±0.10	16.18	yes	5
AS568-205	0.421 ±0.005	0.139 ±0.004	0.699	10.69 ±0.13	3.53 ±0.10	17.75	yes	5
AS568-206	0.484 ±0.005	0.139 ±0.004	0.762	12.29 ±0.13	3.53 ±0.10	19.35	yes	5
AS568-207	0.546 ±0.007	0.139 ±0.004	0.824	13.87 ±0.18	3.53 ±0.10	20.93	yes	5
AS568-208	0.609 ±0.009	0.139 ±0.004	0.887	15.47 ±0.23	3.53 ±0.10	22.53	yes	5
AS568-209	0.671 ±0.009	0.139 ±0.004	0.949	17.04 ±0.23	3.53 ±0.10	24.10	yes	5
AS568-210	0.734 ±0.010	0.139 ±0.004	1.012	18.64 ±0.25	3.53 ±0.10	25.70	yes	5
AS568-211	0.796 ±0.010	0.139 ±0.004	1.074	20.22 ±0.25	3.53 ±0.10	27.28	yes	5
AS568-212	0.859 ±0.010	0.139 ±0.004	1.137	21.82 ±0.25	3.53 ±0.10	28.88	yes	5
AS568-213	0.921 ±0.010	0.139 ±0.004	1.199	23.39 ±0.25	3.53 ±0.10	30.45	yes	5
AS568-214	0.984 ±0.010	0.139 ±0.004	1.262	24.99 ±0.25	3.53 ±0.10	32.05	yes	5
AS568-215	1.046 ±0.010	0.139 ±0.004	1.324	26.57 ±0.25	3.53 ±0.10	33.63	yes	5
AS568-216	1.109 ±0.012	0.139 ±0.004	1.387	28.17 ±0.30	3.53 ±0.10	35.23	yes	5
AS568-217	1.171 ±0.012	0.139 ±0.004	1.449	29.74 ±0.30	3.53 ±0.10	36.80	yes	5
AS568-218	1.234 ±0.012	0.139 ±0.004	1.512	31.34 ±0.30	3.53 ±0.10	38.40	yes	5
AS568-219	1.296 ±0.012	0.139 ±0.004	1.574	32.92 ±0.30	3.53 ±0.10	39.98	yes	5
AS568-220	1.359 ±0.012	0.139 ±0.004	1.637	34.52 ±0.30	3.53 ±0.10	41.58	yes	5
AS568-221	1.421 ±0.012	0.139 ±0.004	1.699	36.09 ±0.30	3.53 ±0.10	43.15	yes	5
AS568-222	1.484 ±0.015	0.139 ±0.004	1.762	37.69 ±0.38	3.53 ±0.10	44.75	yes	5
AS568-223	1.609 ±0.015	0.139 ±0.004	1.887	40.87 ±0.38	3.53 ±0.10	47.93	yes	5
AS568-224	1.734 ±0.015	0.139 ±0.004	2.012	44.04 ±0.38	3.53 ±0.10	51.10	yes	5
AS568-225	1.859 ±0.018	0.139 ±0.004	2.137	47.22 ±0.46	3.53 ±0.10	54.28	yes	5
AS568-226	1.984 ±0.018	0.139 ±0.004	2.262	50.39 ±0.46	3.53 ±0.10	57.45	yes	5
AS568-227	2.109 ±0.018	0.139 ±0.004	2.387	53.57 ±0.46	3.53 ±0.10	60.63	yes	5
AS568-228	2.234 ±0.020	0.139 ±0.004	2.512	56.74 ±0.51	3.53 ±0.10	63.80	yes	5
AS568-229	2.359 ±0.020	0.139 ±0.004	2.637	59.92 ±0.51	3.53 ±0.10	66.98	yes	5
AS568-230	2.484 ±0.020	0.139 ±0.004	2.762	63.09 ±0.51	3.53 ±0.10	70.15	yes	5
AS568-231	2.609 ±0.020	0.139 ±0.004	2.887	66.27 ±0.51	3.53 ±0.10	73.33	yes	5
AS568-232	2.734 ±0.024	0.139 ±0.004	3.012	69.44 ±0.61	3.53 ±0.10	76.50	yes	5
AS568-233	2.859 ±0.024	0.139 ±0.004	3.137	72.62 ±0.61	3.53 ±0.10	79.68	yes	5
AS568-234	2.984 ±0.024	0.139 ±0.004	3.262	75.79 ±0.61	3.53 ±0.10	82.85	yes	5
AS568-235	3.109 ±0.024	0.139 ±0.004	3.387	78.97 ±0.61	3.53 ±0.10	86.03	yes	5
AS568-236	3.234 ±0.024	0.139 ±0.004	3.512	82.14 ±0.61	3.53 ±0.10	89.20	yes	5
AS568-237	3.359 ±0.024	0.139 ±0.004	3.637	85.32 ±0.61	3.53 ±0.10	92.38	yes	5
AS568-238	3.484 ±0.024	0.139 ±0.004	3.762	88.49 ±0.61	3.53 ±0.10	95.55	yes	5
AS568-239	3.609 ±0.028	0.139 ±0.004	3.887	91.67 ±0.71	3.53 ±0.10	98.73	yes	5
AS568-240	3.734 ±0.028	0.139 ±0.004	4.012	94.84 ±0.71	3.53 ±0.10	101.90	yes	5
AS568-241	3.859 ±0.028	0.139 ±0.004	4.137	98.02 ±0.71	3.53 ±0.10	105.08	yes	5
AS568-242	3.984 ±0.028	0.139 ±0.004	4.262	101.19 ±0.71	3.53 ±0.10	108.25	yes	5
AS568-243	4.109 ±0.028	0.139 ±0.004	4.387	104.37 ±0.71	3.53 ±0.10	111.43	yes	5
AS568-244	4.234 ±0.030	0.139 ±0.004	4.512	107.54 ±0.76	3.53 ±0.10	114.60	yes	5
AS568-245	4.359 ±0.030	0.139 ±0.004	4.637	110.72 ±0.76	3.53 ±0.10	117.78	yes	5
AS568-246	4.484 ±0.030	0.139 ±0.004	4.762	113.89 ±0.76	3.53 ±0.10	120.95	yes	5
AS568-247	4.609 ±0.030	0.139 ±0.004	4.887	117.07 ±0.76	3.53 ±0.10	124.13	yes	5
AS568-248	4.734 ±0.030	0.139 ±0.004	5.012	120.24 ±0.76	3.53 ±0.10	127.30	yes	5
AS568-249	4.859 ±0.035	0.139 ±0.004	5.137	123.42 ±0.89	3.53 ±0.10	130.48	yes	5
AS568-250	4.984 ±0.035	0.139 ±0.004	5.262	126.59 ±0.89	3.53 ±0.10	133.65	yes	5
AS568-251	5.109 ±0.035	0.139 ±0.004	5.387	129.77 ±0.89	3.53 ±0.10	136.83	yes	5
AS568-252	5.234 ±0.035	0.139 ±0.004	5.512	132.94 ±0.89	3.53 ±0.10	140.00	yes	5
AS568-253	5.359 ±0.035	0.139 ±0.004	5.637	136.12 ±0.89	3.53 ±0.10	143.18	yes	5
AS568-254	5.484 ±0.035	0.139 ±0.004	5.762	139.29 ±0.89	3.53 ±0.10	146.35	yes	5
AS568-255	5.609 ±0.035	0.139 ±0.004	5.887	142.47 ±0.89	3.53 ±0.10	149.53	yes	5
AS568-256	5.734 ±0.035	0.139 ±0.004	6.012	145.64 ±0.89	3.53 ±0.10	152.70	yes	5
AS568-257	5.859 ±0.035	0.139 ±0.004	6.137	148.82 ±0.89	3.53 ±0.10	155.88	yes	5
AS568-258	5.984 ±0.035	0.139 ±0.004	6.262	151.99 ±0.89	3.53 ±0.10	159.05	yes	5
AS568-259	6.234 ±0.040	0.139 ±0.004	6.512	158.34 ±1.02	3.53 ±0.10	165.40	yes	5
AS568-260	6.484 ±0.040	0.139 ±0.004	6.762	164.69 ±1.02	3.53 ±0.10	171.75	yes	5
AS568-261	6.734 ±0.040	0.139 ±0.004	7.012	171.04 ±1.02	3.53 ±0.10	178.10	yes	5
AS568-262	6.984 ±0.040	0.139 ±0.004	7.262	177.39 ±1.02	3.53 ±0.10	184.45	yes	5
AS568-263	7.234 ±0.045	0.139 ±0.004	7.512	183.74 ±1.14	3.53 ±0.10	190.80	yes	5
AS568-264	7.484 ±0.045	0.139 ±0.004	7.762	190.09 ±1.14	3.53 ±0.10	197.15	yes	5
AS568-265	7.734 ±0.045	0.139 ±0.004	8.012	196.44 ±1.14	3.53 ±0.10	203.50	yes	5
AS568-266	7.984 ±0.045	0.139 ±0.004	8.262	202.79 ±1.14	3.53 ±0.10	209.85	yes	5
AS568-267	8.234 ±0.050	0.139 ±0.004	8.512	209.14 ±1.27	3.53 ±0.10	216.20	yes	5
AS568-268	8.484 ±0.050	0.139 ±0.004	8.762	215.49 ±1.27	3.53 ±0.10	222.55	yes	5
AS568-269	8.734 ±0.050	0.139 ±0.004	9.012	221.84 ±1.27	3.53 ±0.10	228.90	yes	5
AS568-270	8.984 ±0.050	0.139 ±0.004	9.262	228.19 ±1.27	3.53 ±0.10	235.25	yes	5
AS568-271	9.234 ±0.055	0.139 ±0.004	9.512	234.54 ±1.40	3.53 ±0.10	241.60	yes	5
AS568-272	9.484 ±0.055	0.139 ±0.004	9.762	240.89 ±1.40	3.53 ±0.10	247.95	yes	5
AS568-273	9.734 ±0.055	0.139 ±0.004	10.012	247.24 ±1.40	3.53 ±0.10	254.30	yes	5
AS568-274	9.984 ±0.055	0.139 ±0.004	10.262	253.59 ±1.40	3.53 ±0.10	260.65	yes	5
AS568-275	10.484 ±0.055	0.139 ±0.004	10.762	266.29 ±1.40	3.53 ±0.10	273.35	yes	5
AS568-276	10.984 ±0.065	0.139 ±0.004	11.262	278.99 ±1.65	3.53 ±0.10	286.05	yes	5
AS568-277	11.484 ±0.065	0.139 ±0.004	11.762	291.69 ±1.65	3.53 ±0.10	298.75	yes	5
AS568-278	11.984 ±0.065	0.139 ±0.004	12.262	304.39 ±1.65	3.53 ±0.10	311.45	yes	5
AS568-279	12.984 ±0.065	0.139 ±0.004	13.262	329.79 ±1.65	3.53 ±0.10	336.85	yes	5
AS568-280	13.984 ±0.065	0.139 ±0.004	14.262	355.19 ±1.65	3.53 ±0.10	362.25	yes	5
AS568-281	14.984 ±0.065	0.139 ±0.004	15.262	380.59 ±1.65	3.53 ±0.10	387.65	yes	5
AS568-282	15.955 ±0.075	0.139 ±0.004	16.233	405.26 ±1.91	3.53 ±0.10	412.32	yes	5
AS568-283	16.955 ±0.080	0.139 ±0.004	17.233	430.66 ±2.03	3.53 ±0.10	437.72	yes	5
AS568-284	17.955 ±0.085	0.139 ±0.004	18.233	456.06 ±2.16	3.53 ±0.10	463.12	yes	5

Where the sources disagree in the 2xx series

AS568-282: Published inside diameters differ: 15.955 in (as568-arc), 15.984 in (as568-oringseal), 15.955 in (as568-parco), 15.955 in (as568-savvy). The figure printed is 15.955 in, carried by 3 of the 4 sources.
AS568-283: Published inside diameters differ: 16.955 in (as568-arc), 16.984 in (as568-oringseal), 16.955 in (as568-parco), 16.955 in (as568-savvy). The figure printed is 16.955 in, carried by 3 of the 4 sources.
AS568-284: Published inside diameters differ: 17.955 in (as568-arc), 17.984 in (as568-oringseal), 17.955 in (as568-parco), 17.955 in (as568-savvy). The figure printed is 17.955 in, carried by 3 of the 4 sources.

87 sizes · cross section 0.210" (5.33 mm) ±0.005"

3xx series

Heavy hydraulic and high pressure. Standard dash numbers 309 to 395.

AS568 3xx series dash numbers with inside diameter, cross section and outside diameter, each with its published tolerance.
Dash	ID (in)	CS (in)	OD (in)	ID (mm)	CS (mm)	OD (mm)	AS568B	Sources
AS568-309	0.412 ±0.005	0.210 ±0.005	0.832	10.46 ±0.13	5.33 ±0.13	21.12	yes	5
AS568-310	0.475 ±0.005	0.210 ±0.005	0.895	12.07 ±0.13	5.33 ±0.13	22.73	yes	5
AS568-311	0.537 ±0.007	0.210 ±0.005	0.957	13.64 ±0.18	5.33 ±0.13	24.30	yes	5
AS568-312	0.600 ±0.009	0.210 ±0.005	1.020	15.24 ±0.23	5.33 ±0.13	25.90	yes	5
AS568-313	0.662 ±0.009	0.210 ±0.005	1.082	16.81 ±0.23	5.33 ±0.13	27.47	yes	5
AS568-314	0.725 ±0.010	0.210 ±0.005	1.145	18.42 ±0.25	5.33 ±0.13	29.08	yes	5
AS568-315	0.787 ±0.010	0.210 ±0.005	1.207	19.99 ±0.25	5.33 ±0.13	30.65	yes	5
AS568-316	0.850 ±0.010	0.210 ±0.005	1.270	21.59 ±0.25	5.33 ±0.13	32.25	yes	5
AS568-317	0.912 ±0.010	0.210 ±0.005	1.332	23.16 ±0.25	5.33 ±0.13	33.82	yes	5
AS568-318	0.975 ±0.010	0.210 ±0.005	1.395	24.77 ±0.25	5.33 ±0.13	35.43	yes	5
AS568-319	1.037 ±0.010	0.210 ±0.005	1.457	26.34 ±0.25	5.33 ±0.13	37.00	yes	5
AS568-320	1.100 ±0.012	0.210 ±0.005	1.520	27.94 ±0.30	5.33 ±0.13	38.60	yes	5
AS568-321	1.162 ±0.012	0.210 ±0.005	1.582	29.51 ±0.30	5.33 ±0.13	40.17	yes	5
AS568-322	1.225 ±0.012	0.210 ±0.005	1.645	31.12 ±0.30	5.33 ±0.13	41.78	yes	5
AS568-323	1.287 ±0.012	0.210 ±0.005	1.707	32.69 ±0.30	5.33 ±0.13	43.35	yes	5
AS568-324	1.350 ±0.012	0.210 ±0.005	1.770	34.29 ±0.30	5.33 ±0.13	44.95	yes	5
AS568-325	1.475 ±0.015	0.210 ±0.005	1.895	37.47 ±0.38	5.33 ±0.13	48.13	yes	5
AS568-326	1.600 ±0.015	0.210 ±0.005	2.020	40.64 ±0.38	5.33 ±0.13	51.30	yes	5
AS568-327	1.725 ±0.015	0.210 ±0.005	2.145	43.82 ±0.38	5.33 ±0.13	54.48	yes	5
AS568-328	1.850 ±0.015	0.210 ±0.005	2.270	46.99 ±0.38	5.33 ±0.13	57.65	yes	5
AS568-329	1.975 ±0.018	0.210 ±0.005	2.395	50.17 ±0.46	5.33 ±0.13	60.83	yes	5
AS568-330	2.100 ±0.018	0.210 ±0.005	2.520	53.34 ±0.46	5.33 ±0.13	64.00	yes	5
AS568-331	2.225 ±0.018	0.210 ±0.005	2.645	56.52 ±0.46	5.33 ±0.13	67.18	yes	5
AS568-332	2.350 ±0.018	0.210 ±0.005	2.770	59.69 ±0.46	5.33 ±0.13	70.35	yes	5
AS568-333	2.475 ±0.020	0.210 ±0.005	2.895	62.87 ±0.51	5.33 ±0.13	73.53	yes	5
AS568-334	2.600 ±0.020	0.210 ±0.005	3.020	66.04 ±0.51	5.33 ±0.13	76.70	yes	5
AS568-335	2.725 ±0.020	0.210 ±0.005	3.145	69.22 ±0.51	5.33 ±0.13	79.88	yes	5
AS568-336	2.850 ±0.020	0.210 ±0.005	3.270	72.39 ±0.51	5.33 ±0.13	83.05	yes	5
AS568-337	2.975 ±0.024	0.210 ±0.005	3.395	75.57 ±0.61	5.33 ±0.13	86.23	yes	5
AS568-338	3.100 ±0.024	0.210 ±0.005	3.520	78.74 ±0.61	5.33 ±0.13	89.40	yes	5
AS568-339	3.225 ±0.024	0.210 ±0.005	3.645	81.92 ±0.61	5.33 ±0.13	92.58	yes	5
AS568-340	3.350 ±0.024	0.210 ±0.005	3.770	85.09 ±0.61	5.33 ±0.13	95.75	yes	5
AS568-341	3.475 ±0.024	0.210 ±0.005	3.895	88.27 ±0.61	5.33 ±0.13	98.93	yes	5
AS568-342	3.600 ±0.028	0.210 ±0.005	4.020	91.44 ±0.71	5.33 ±0.13	102.10	yes	5
AS568-343	3.725 ±0.028	0.210 ±0.005	4.145	94.62 ±0.71	5.33 ±0.13	105.28	yes	5
AS568-344	3.850 ±0.028	0.210 ±0.005	4.270	97.79 ±0.71	5.33 ±0.13	108.45	yes	5
AS568-345	3.975 ±0.028	0.210 ±0.005	4.395	100.97 ±0.71	5.33 ±0.13	111.63	yes	5
AS568-346	4.100 ±0.028	0.210 ±0.005	4.520	104.14 ±0.71	5.33 ±0.13	114.80	yes	5
AS568-347	4.225 ±0.030	0.210 ±0.005	4.645	107.32 ±0.76	5.33 ±0.13	117.98	yes	5
AS568-348	4.350 ±0.030	0.210 ±0.005	4.770	110.49 ±0.76	5.33 ±0.13	121.15	yes	5
AS568-349	4.475 ±0.030	0.210 ±0.005	4.895	113.67 ±0.76	5.33 ±0.13	124.33	yes	5
AS568-350	4.600 ±0.030	0.210 ±0.005	5.020	116.84 ±0.76	5.33 ±0.13	127.50	yes	5
AS568-351	4.725 ±0.030	0.210 ±0.005	5.145	120.02 ±0.76	5.33 ±0.13	130.68	yes	5
AS568-352	4.850 ±0.030	0.210 ±0.005	5.270	123.19 ±0.76	5.33 ±0.13	133.85	yes	5
AS568-353	4.975 ±0.037	0.210 ±0.005	5.395	126.37 ±0.94	5.33 ±0.13	137.03	yes	5
AS568-354	5.100 ±0.037	0.210 ±0.005	5.520	129.54 ±0.94	5.33 ±0.13	140.20	yes	5
AS568-355	5.225 ±0.037	0.210 ±0.005	5.645	132.72 ±0.94	5.33 ±0.13	143.38	yes	5
AS568-356	5.350 ±0.037	0.210 ±0.005	5.770	135.89 ±0.94	5.33 ±0.13	146.55	yes	5
AS568-357	5.475 ±0.037	0.210 ±0.005	5.895	139.07 ±0.94	5.33 ±0.13	149.73	yes	5
AS568-358	5.600 ±0.037	0.210 ±0.005	6.020	142.24 ±0.94	5.33 ±0.13	152.90	yes	5
AS568-359	5.725 ±0.037	0.210 ±0.005	6.145	145.42 ±0.94	5.33 ±0.13	156.08	yes	5
AS568-360	5.850 ±0.037	0.210 ±0.005	6.270	148.59 ±0.94	5.33 ±0.13	159.25	yes	5
AS568-361	5.975 ±0.037	0.210 ±0.005	6.395	151.77 ±0.94	5.33 ±0.13	162.43	yes	5
AS568-362	6.225 ±0.040	0.210 ±0.005	6.645	158.12 ±1.02	5.33 ±0.13	168.78	yes	5
AS568-363	6.475 ±0.040	0.210 ±0.005	6.895	164.47 ±1.02	5.33 ±0.13	175.13	yes	5
AS568-364	6.725 ±0.040	0.210 ±0.005	7.145	170.82 ±1.02	5.33 ±0.13	181.48	yes	5
AS568-365	6.975 ±0.040	0.210 ±0.005	7.395	177.17 ±1.02	5.33 ±0.13	187.83	yes	5
AS568-366	7.225 ±0.045	0.210 ±0.005	7.645	183.52 ±1.14	5.33 ±0.13	194.18	yes	5
AS568-367	7.475 ±0.045	0.210 ±0.005	7.895	189.87 ±1.14	5.33 ±0.13	200.53	yes	5
AS568-368	7.725 ±0.045	0.210 ±0.005	8.145	196.22 ±1.14	5.33 ±0.13	206.88	yes	5
AS568-369	7.975 ±0.045	0.210 ±0.005	8.395	202.57 ±1.14	5.33 ±0.13	213.23	yes	5
AS568-370	8.225 ±0.050	0.210 ±0.005	8.645	208.92 ±1.27	5.33 ±0.13	219.58	yes	5
AS568-371	8.475 ±0.050	0.210 ±0.005	8.895	215.27 ±1.27	5.33 ±0.13	225.93	yes	5
AS568-372	8.725 ±0.050	0.210 ±0.005	9.145	221.62 ±1.27	5.33 ±0.13	232.28	yes	5
AS568-373	8.975 ±0.050	0.210 ±0.005	9.395	227.97 ±1.27	5.33 ±0.13	238.63	yes	5
AS568-374	9.225 ±0.055	0.210 ±0.005	9.645	234.32 ±1.40	5.33 ±0.13	244.98	yes	5
AS568-375	9.475 ±0.055	0.210 ±0.005	9.895	240.67 ±1.40	5.33 ±0.13	251.33	yes	5
AS568-376	9.725 ±0.055	0.210 ±0.005	10.145	247.02 ±1.40	5.33 ±0.13	257.68	yes	5
AS568-377	9.975 ±0.055	0.210 ±0.005	10.395	253.37 ±1.40	5.33 ±0.13	264.03	yes	5
AS568-378	10.475 ±0.060	0.210 ±0.005	10.895	266.07 ±1.52	5.33 ±0.13	276.73	yes	5
AS568-379	10.975 ±0.060	0.210 ±0.005	11.395	278.77 ±1.52	5.33 ±0.13	289.43	yes	5
AS568-380	11.475 ±0.065	0.210 ±0.005	11.895	291.47 ±1.65	5.33 ±0.13	302.13	yes	5
AS568-381	11.975 ±0.065	0.210 ±0.005	12.395	304.17 ±1.65	5.33 ±0.13	314.83	yes	5
AS568-382	12.975 ±0.065	0.210 ±0.005	13.395	329.57 ±1.65	5.33 ±0.13	340.23	yes	5
AS568-383	13.975 ±0.070	0.210 ±0.005	14.395	354.97 ±1.78	5.33 ±0.13	365.63	yes	5
AS568-384	14.975 ±0.070	0.210 ±0.005	15.395	380.37 ±1.78	5.33 ±0.13	391.03	yes	5
AS568-385	15.955 ±0.075	0.210 ±0.005	16.375	405.26 ±1.91	5.33 ±0.13	415.92	yes	5
AS568-386	16.955 ±0.080	0.210 ±0.005	17.375	430.66 ±2.03	5.33 ±0.13	441.32	yes	5
AS568-387	17.955 ±0.085	0.210 ±0.005	18.375	456.06 ±2.16	5.33 ±0.13	466.72	yes	5
AS568-388	18.955 ±0.090	0.210 ±0.005	19.375	481.46 ±2.29	5.33 ±0.13	492.12	yes	4
AS568-389	19.955 ±0.095	0.210 ±0.005	20.375	506.86 ±2.41	5.33 ±0.13	517.52	yes	4
AS568-390	20.955 ±0.095	0.210 ±0.005	21.375	532.26 ±2.41	5.33 ±0.13	542.92	yes	4
AS568-391	21.955	0.210 ±0.005	22.375	557.66	5.33 ±0.13	568.32	yes	4
AS568-392	22.940 ±0.105	0.210 ±0.005	23.360	582.68 ±2.67	5.33 ±0.13	593.34	yes	4
AS568-393	23.940 ±0.110	0.210 ±0.005	24.360	608.08 ±2.79	5.33 ±0.13	618.74	yes	4
AS568-394	24.940 ±0.115	0.210 ±0.005	25.360	633.48 ±2.92	5.33 ±0.13	644.14	yes	4
AS568-395	25.940 ±0.120	0.210 ±0.005	26.360	658.88 ±3.05	5.33 ±0.13	669.54	yes	4

Where the sources disagree in the 3xx series

AS568-385: Published inside diameters differ: 15.955 in (as568-arc), 15.975 in (as568-oringseal), 15.955 in (as568-parco), 15.955 in (as568-savvy). The figure printed is 15.955 in, carried by 3 of the 4 sources.
AS568-386: Published inside diameters differ: 16.955 in (as568-arc), 16.975 in (as568-oringseal), 16.955 in (as568-parco), 16.955 in (as568-savvy). The figure printed is 16.955 in, carried by 3 of the 4 sources.
AS568-387: Published inside diameters differ: 17.955 in (as568-arc), 17.975 in (as568-oringseal), 17.955 in (as568-parco), 17.955 in (as568-savvy). The figure printed is 17.955 in, carried by 3 of the 4 sources.
AS568-391: No inside-diameter tolerance is printed for this size: the sources do not agree and none of the readings has a second table behind it - plus or minus 0.095 in (as568-arc), plus or minus 0.1 in (as568-parco).

76 sizes · cross section 0.275" (6.99 mm) ±0.006"

4xx series

Industrial flange and piping. Standard dash numbers 425 to 475.

AS568 4xx series dash numbers with inside diameter, cross section and outside diameter, each with its published tolerance.
Dash	ID (in)	CS (in)	OD (in)	ID (mm)	CS (mm)	OD (mm)	AS568B	Sources
AS568-400	1.350	0.275	1.900	34.29	6.99	48.27	catalogue size	2
AS568-401	1.475	0.275	2.025	37.47	6.99	51.45	catalogue size	2
AS568-402	1.600	0.275	2.150	40.64	6.99	54.62	catalogue size	2
AS568-403	1.725	0.275	2.275	43.82	6.99	57.80	catalogue size	2
AS568-404	1.850	0.275	2.400	46.99	6.99	60.97	catalogue size	2
AS568-405	1.975	0.275	2.525	50.17	6.99	64.15	catalogue size	2
AS568-406	2.100	0.275	2.650	53.34	6.99	67.32	catalogue size	2
AS568-407	2.225	0.275	2.775	56.52	6.99	70.50	catalogue size	2
AS568-408	2.350	0.275	2.900	59.69	6.99	73.67	catalogue size	2
AS568-409	2.475	0.275	3.025	62.87	6.99	76.85	catalogue size	2
AS568-410	2.600	0.275	3.150	66.04	6.99	80.02	catalogue size	2
AS568-411	2.725	0.275	3.275	69.22	6.99	83.20	catalogue size	2
AS568-412	2.850	0.275	3.400	72.39	6.99	86.37	catalogue size	2
AS568-413	2.975	0.275	3.525	75.57	6.99	89.55	catalogue size	2
AS568-414	3.100	0.275	3.650	78.74	6.99	92.72	catalogue size	2
AS568-415	3.225	0.275	3.775	81.92	6.99	95.90	catalogue size	2
AS568-416	3.350	0.275	3.900	85.09	6.99	99.07	catalogue size	2
AS568-417	3.475	0.275	4.025	88.27	6.99	102.25	catalogue size	2
AS568-418	3.600	0.275	4.150	91.44	6.99	105.42	catalogue size	2
AS568-419	3.725	0.275	4.275	94.62	6.99	108.60	catalogue size	2
AS568-420	3.850	0.275	4.400	97.79	6.99	111.77	catalogue size	2
AS568-421	3.975	0.275	4.525	100.97	6.99	114.95	catalogue size	2
AS568-422	4.100	0.275	4.650	104.14	6.99	118.12	catalogue size	2
AS568-423	4.225	0.275	4.775	107.32	6.99	121.30	catalogue size	2
AS568-424	4.350	0.275	4.900	110.49	6.99	124.47	catalogue size	2
AS568-425	4.475 ±0.033	0.275 ±0.006	5.025	113.67 ±0.84	6.99 ±0.15	127.65	yes	5
AS568-426	4.600 ±0.033	0.275 ±0.006	5.150	116.84 ±0.84	6.99 ±0.15	130.82	yes	5
AS568-427	4.725 ±0.033	0.275 ±0.006	5.275	120.02 ±0.84	6.99 ±0.15	134.00	yes	5
AS568-428	4.850 ±0.033	0.275 ±0.006	5.400	123.19 ±0.84	6.99 ±0.15	137.17	yes	5
AS568-429	4.975 ±0.037	0.275 ±0.006	5.525	126.37 ±0.94	6.99 ±0.15	140.35	yes	5
AS568-430	5.100 ±0.037	0.275 ±0.006	5.650	129.54 ±0.94	6.99 ±0.15	143.52	yes	5
AS568-431	5.225 ±0.037	0.275 ±0.006	5.775	132.72 ±0.94	6.99 ±0.15	146.70	yes	5
AS568-432	5.350 ±0.037	0.275 ±0.006	5.900	135.89 ±0.94	6.99 ±0.15	149.87	yes	5
AS568-433	5.475 ±0.037	0.275 ±0.006	6.025	139.07 ±0.94	6.99 ±0.15	153.05	yes	5
AS568-434	5.600 ±0.037	0.275 ±0.006	6.150	142.24 ±0.94	6.99 ±0.15	156.22	yes	5
AS568-435	5.725 ±0.037	0.275 ±0.006	6.275	145.42 ±0.94	6.99 ±0.15	159.40	yes	5
AS568-436	5.850 ±0.037	0.275 ±0.006	6.400	148.59 ±0.94	6.99 ±0.15	162.57	yes	5
AS568-437	5.975 ±0.037	0.275 ±0.006	6.525	151.77 ±0.94	6.99 ±0.15	165.75	yes	5
AS568-438	6.225 ±0.040	0.275 ±0.006	6.775	158.12 ±1.02	6.99 ±0.15	172.10	yes	5
AS568-439	6.475 ±0.040	0.275 ±0.006	7.025	164.47 ±1.02	6.99 ±0.15	178.45	yes	5
AS568-440	6.725 ±0.040	0.275 ±0.006	7.275	170.82 ±1.02	6.99 ±0.15	184.80	yes	5
AS568-441	6.975 ±0.040	0.275 ±0.006	7.525	177.17 ±1.02	6.99 ±0.15	191.15	yes	5
AS568-442	7.225 ±0.045	0.275 ±0.006	7.775	183.52 ±1.14	6.99 ±0.15	197.50	yes	5
AS568-443	7.475 ±0.045	0.275 ±0.006	8.025	189.87 ±1.14	6.99 ±0.15	203.85	yes	5
AS568-444	7.725 ±0.045	0.275 ±0.006	8.275	196.22 ±1.14	6.99 ±0.15	210.20	yes	5
AS568-445	7.975 ±0.045	0.275 ±0.006	8.525	202.57 ±1.14	6.99 ±0.15	216.55	yes	5
AS568-446	8.475 ±0.055	0.275 ±0.006	9.025	215.27 ±1.40	6.99 ±0.15	229.25	yes	5
AS568-447	8.975 ±0.055	0.275 ±0.006	9.525	227.97 ±1.40	6.99 ±0.15	241.95	yes	5
AS568-448	9.475 ±0.055	0.275 ±0.006	10.025	240.67 ±1.40	6.99 ±0.15	254.65	yes	5
AS568-449	9.975 ±0.055	0.275 ±0.006	10.525	253.37 ±1.40	6.99 ±0.15	267.35	yes	5
AS568-450	10.475 ±0.060	0.275 ±0.006	11.025	266.07 ±1.52	6.99 ±0.15	280.05	yes	5
AS568-451	10.975 ±0.060	0.275 ±0.006	11.525	278.77 ±1.52	6.99 ±0.15	292.75	yes	5
AS568-452	11.475 ±0.060	0.275 ±0.006	12.025	291.47 ±1.52	6.99 ±0.15	305.45	yes	5
AS568-453	11.975 ±0.060	0.275 ±0.006	12.525	304.17 ±1.52	6.99 ±0.15	318.15	yes	5
AS568-454	12.475 ±0.060	0.275 ±0.006	13.025	316.87 ±1.52	6.99 ±0.15	330.85	yes	5
AS568-455	12.975 ±0.060	0.275 ±0.006	13.525	329.57 ±1.52	6.99 ±0.15	343.55	yes	5
AS568-456	13.475 ±0.070	0.275 ±0.006	14.025	342.27 ±1.78	6.99 ±0.15	356.25	yes	5
AS568-457	13.975 ±0.070	0.275 ±0.006	14.525	354.97 ±1.78	6.99 ±0.15	368.95	yes	5
AS568-458	14.475 ±0.070	0.275 ±0.006	15.025	367.67 ±1.78	6.99 ±0.15	381.65	yes	5
AS568-459	14.975 ±0.070	0.275 ±0.006	15.525	380.37 ±1.78	6.99 ±0.15	394.35	yes	5
AS568-460	15.475 ±0.070	0.275 ±0.006	16.025	393.07 ±1.78	6.99 ±0.15	407.05	yes	5
AS568-461	15.955 ±0.075	0.275 ±0.006	16.505	405.26 ±1.91	6.99 ±0.15	419.24	yes	5
AS568-462	16.455 ±0.075	0.275 ±0.006	17.005	417.96 ±1.91	6.99 ±0.15	431.94	yes	5
AS568-463	16.955 ±0.080	0.275 ±0.006	17.505	430.66 ±2.03	6.99 ±0.15	444.64	yes	5
AS568-464	17.455 ±0.085	0.275 ±0.006	18.005	443.36 ±2.16	6.99 ±0.15	457.34	yes	5
AS568-465	17.955 ±0.085	0.275 ±0.006	18.505	456.06 ±2.16	6.99 ±0.15	470.04	yes	5
AS568-466	18.455 ±0.085	0.275 ±0.006	19.005	468.76 ±2.16	6.99 ±0.15	482.74	yes	5
AS568-467	18.955 ±0.090	0.275 ±0.006	19.505	481.46 ±2.29	6.99 ±0.15	495.44	yes	5
AS568-468	19.455 ±0.090	0.275 ±0.006	20.005	494.16 ±2.29	6.99 ±0.15	508.14	yes	5
AS568-469	19.955 ±0.095	0.275 ±0.006	20.505	506.86 ±2.41	6.99 ±0.15	520.84	yes	5
AS568-470	20.955 ±0.095	0.275 ±0.006	21.505	532.26 ±2.41	6.99 ±0.15	546.24	yes	5
AS568-471	21.955 ±0.100	0.275 ±0.006	22.505	557.66 ±2.54	6.99 ±0.15	571.64	yes	5
AS568-472	22.940 ±0.105	0.275 ±0.006	23.490	582.68 ±2.67	6.99 ±0.15	596.66	yes	5
AS568-473	23.940 ±0.110	0.275 ±0.006	24.490	608.08 ±2.79	6.99 ±0.15	622.06	yes	5
AS568-474	24.940 ±0.115	0.275 ±0.006	25.490	633.48 ±2.92	6.99 ±0.15	647.46	yes	5
AS568-475	25.940 ±0.120	0.275 ±0.006	26.490	658.88 ±3.05	6.99 ±0.15	672.86	yes	5

Where the sources disagree in the 4xx series

AS568-400: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.012 in) and a single chart is not enough to print a tolerance from.
AS568-401: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.015 in) and a single chart is not enough to print a tolerance from.
AS568-402: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.015 in) and a single chart is not enough to print a tolerance from.
AS568-403: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.015 in) and a single chart is not enough to print a tolerance from.
AS568-404: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.015 in) and a single chart is not enough to print a tolerance from.
AS568-405: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.018 in) and a single chart is not enough to print a tolerance from.
AS568-406: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.018 in) and a single chart is not enough to print a tolerance from.
AS568-407: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.018 in) and a single chart is not enough to print a tolerance from.
AS568-408: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.018 in) and a single chart is not enough to print a tolerance from.
AS568-409: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.02 in) and a single chart is not enough to print a tolerance from.
AS568-410: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.02 in) and a single chart is not enough to print a tolerance from.
AS568-411: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.02 in) and a single chart is not enough to print a tolerance from.
AS568-412: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.02 in) and a single chart is not enough to print a tolerance from.
AS568-413: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.024 in) and a single chart is not enough to print a tolerance from.
AS568-414: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.024 in) and a single chart is not enough to print a tolerance from.
AS568-415: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.024 in) and a single chart is not enough to print a tolerance from.
AS568-416: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.024 in) and a single chart is not enough to print a tolerance from.
AS568-417: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.024 in) and a single chart is not enough to print a tolerance from.
AS568-418: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.028 in) and a single chart is not enough to print a tolerance from.
AS568-419: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.028 in) and a single chart is not enough to print a tolerance from.
AS568-420: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.028 in) and a single chart is not enough to print a tolerance from.
AS568-421: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.028 in) and a single chart is not enough to print a tolerance from.
AS568-422: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.028 in) and a single chart is not enough to print a tolerance from.
AS568-423: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.03 in) and a single chart is not enough to print a tolerance from.
AS568-424: No inside-diameter tolerance is printed for this size. Only one of the sources publishes one (as568-arc, plus or minus 0.03 in) and a single chart is not enough to print a tolerance from.
AS568-446: Published inside diameters differ: 8.475 in (as568-arc), 8.225 in (as568-oringseal), 8.475 in (as568-parco), 8.475 in (as568-savvy). The figure printed is 8.475 in, carried by 3 of the 4 sources.
AS568-447: Published inside diameters differ: 8.975 in (as568-arc), 8.475 in (as568-oringseal), 8.975 in (as568-parco), 8.975 in (as568-savvy). The figure printed is 8.975 in, carried by 3 of the 4 sources.
AS568-448: Published inside diameters differ: 9.475 in (as568-arc), 8.725 in (as568-oringseal), 9.475 in (as568-parco), 9.475 in (as568-savvy). The figure printed is 9.475 in, carried by 3 of the 4 sources.
AS568-449: Published inside diameters differ: 9.975 in (as568-arc), 8.975 in (as568-oringseal), 9.975 in (as568-parco), 9.975 in (as568-savvy). The figure printed is 9.975 in, carried by 3 of the 4 sources.
AS568-450: Published inside diameters differ: 10.475 in (as568-arc), 9.225 in (as568-oringseal), 10.475 in (as568-parco), 10.475 in (as568-savvy). The figure printed is 10.475 in, carried by 3 of the 4 sources.
AS568-451: Published inside diameters differ: 10.975 in (as568-arc), 9.475 in (as568-oringseal), 10.975 in (as568-parco), 10.975 in (as568-savvy). The figure printed is 10.975 in, carried by 3 of the 4 sources.
AS568-452: Published inside diameters differ: 11.475 in (as568-arc), 9.725 in (as568-oringseal), 11.475 in (as568-parco), 11.475 in (as568-savvy). The figure printed is 11.475 in, carried by 3 of the 4 sources.
AS568-453: Published inside diameters differ: 11.975 in (as568-arc), 9.975 in (as568-oringseal), 11.975 in (as568-parco), 11.975 in (as568-savvy). The figure printed is 11.975 in, carried by 3 of the 4 sources.
AS568-454: Published inside diameters differ: 12.475 in (as568-arc), 10.475 in (as568-oringseal), 12.475 in (as568-parco), 12.475 in (as568-savvy). The figure printed is 12.475 in, carried by 3 of the 4 sources.
AS568-455: Published inside diameters differ: 12.975 in (as568-arc), 10.975 in (as568-oringseal), 12.975 in (as568-parco), 12.975 in (as568-savvy). The figure printed is 12.975 in, carried by 3 of the 4 sources.
AS568-456: Published inside diameters differ: 13.475 in (as568-arc), 11.475 in (as568-oringseal), 13.475 in (as568-parco), 13.457 in (as568-savvy). The figure printed is 13.475 in, carried by 2 of the 4 sources. Outside diameter cross-check: 14.007 in published by as568-savvy against 14.025 in computed.
AS568-457: Published inside diameters differ: 13.975 in (as568-arc), 11.975 in (as568-oringseal), 13.975 in (as568-parco), 13.975 in (as568-savvy). The figure printed is 13.975 in, carried by 3 of the 4 sources.
AS568-458: Published inside diameters differ: 14.475 in (as568-arc), 12.475 in (as568-oringseal), 14.475 in (as568-parco), 14.475 in (as568-savvy). The figure printed is 14.475 in, carried by 3 of the 4 sources.
AS568-459: Published inside diameters differ: 14.975 in (as568-arc), 12.975 in (as568-oringseal), 14.975 in (as568-parco), 14.975 in (as568-savvy). The figure printed is 14.975 in, carried by 3 of the 4 sources.
AS568-460: Published inside diameters differ: 15.475 in (as568-arc), 13.475 in (as568-oringseal), 15.475 in (as568-parco), 15.475 in (as568-savvy). The figure printed is 15.475 in, carried by 3 of the 4 sources.
AS568-461: Published inside diameters differ: 15.955 in (as568-arc), 13.975 in (as568-oringseal), 15.955 in (as568-parco), 15.955 in (as568-savvy). The figure printed is 15.955 in, carried by 3 of the 4 sources.
AS568-462: Published inside diameters differ: 16.455 in (as568-arc), 14.475 in (as568-oringseal), 16.455 in (as568-parco), 16.455 in (as568-savvy). The figure printed is 16.455 in, carried by 3 of the 4 sources.
AS568-463: Published inside diameters differ: 16.955 in (as568-arc), 14.975 in (as568-oringseal), 16.955 in (as568-parco), 16.955 in (as568-savvy). The figure printed is 16.955 in, carried by 3 of the 4 sources.
AS568-464: Published inside diameters differ: 17.455 in (as568-arc), 15.475 in (as568-oringseal), 17.455 in (as568-parco), 17.455 in (as568-savvy). The figure printed is 17.455 in, carried by 3 of the 4 sources.
AS568-465: Published inside diameters differ: 17.955 in (as568-arc), 15.975 in (as568-oringseal), 17.955 in (as568-parco), 17.955 in (as568-savvy). The figure printed is 17.955 in, carried by 3 of the 4 sources.
AS568-466: Published inside diameters differ: 18.455 in (as568-arc), 16.475 in (as568-oringseal), 18.455 in (as568-parco), 18.455 in (as568-savvy). The figure printed is 18.455 in, carried by 3 of the 4 sources.
AS568-467: Published inside diameters differ: 18.955 in (as568-arc), 16.975 in (as568-oringseal), 18.955 in (as568-parco), 18.955 in (as568-savvy). The figure printed is 18.955 in, carried by 3 of the 4 sources.
AS568-468: Published inside diameters differ: 19.455 in (as568-arc), 17.475 in (as568-oringseal), 19.455 in (as568-parco), 19.455 in (as568-savvy). The figure printed is 19.455 in, carried by 3 of the 4 sources.
AS568-469: Published inside diameters differ: 19.955 in (as568-arc), 17.975 in (as568-oringseal), 19.955 in (as568-parco), 19.955 in (as568-savvy). The figure printed is 19.955 in, carried by 3 of the 4 sources.
AS568-470: Published inside diameters differ: 20.955 in (as568-arc), 18.475 in (as568-oringseal), 20.955 in (as568-parco), 20.955 in (as568-savvy). The figure printed is 20.955 in, carried by 3 of the 4 sources.
AS568-471: Published inside diameters differ: 21.955 in (as568-arc), 18.975 in (as568-oringseal), 21.955 in (as568-parco), 21.955 in (as568-savvy). The figure printed is 21.955 in, carried by 3 of the 4 sources.
AS568-472: Published inside diameters differ: 22.94 in (as568-arc), 19.475 in (as568-oringseal), 22.94 in (as568-parco), 22.94 in (as568-savvy). The figure printed is 22.94 in, carried by 3 of the 4 sources.
AS568-473: Published inside diameters differ: 23.94 in (as568-arc), 19.975 in (as568-oringseal), 23.94 in (as568-parco), 23.94 in (as568-savvy). The figure printed is 23.94 in, carried by 3 of the 4 sources.
AS568-474: Published inside diameters differ: 24.94 in (as568-arc), 20.475 in (as568-oringseal), 24.94 in (as568-parco), 24.94 in (as568-savvy). The figure printed is 24.94 in, carried by 3 of the 4 sources.
AS568-475: Published inside diameters differ: 25.94 in (as568-arc), 20.975 in (as568-oringseal), 25.94 in (as568-parco), 25.94 in (as568-savvy). The figure printed is 25.94 in, carried by 3 of the 4 sources.

Tolerances that are not printed

A row with no ± figure is a size where fewer than two of the published tables carry a tolerance, so none is shown. The outside diameter never carries one: it is the inside diameter plus two cross sections, worked out here rather than read from a table.

Where these figures come from

Dimensions are as defined by SAE AS568B (aerospace size standard for O-rings). This site is an independent reference and is not affiliated with, endorsed by or approved by any standards body.

Each row was checked against at least two of these published tables; the Sources column gives the count for that row:

AS568B O-ring size chart (Parco Inc.) - Parco, distributed by All Seals Inc., names Aerospace Standard AS568B, 369 standard sizes (read 2026-08-27)
AS568 O-ring size chart, all dash sizes and tolerances - American Rubber Corporation, edition not stated (read 2026-08-27)
AS568 standard O-ring size chart - Savvy Rubber, edition not stated (read 2026-08-27)
AS568 O-ring size chart (dash numbers, inch and mm) - o-ringseal.com, edition not stated (read 2026-08-27)
AS568 O-ring size conversion with metric O-ring dimensions - Seals Eastern, per-series cross-section tolerances in millimetres (read 2026-08-27)
O-ring tolerances, AS568 standard - Marco Rubber and Plastics, edition not stated (read 2026-08-27)

Dash numbers -400 to -424: listed as AS568 sizes (as568-arc) against listed as AS568 sizes (as568-savvy) against absent; the 4xx series is stated as -425 to -475 (as568-sealseastern) against absent; the chart is stated to hold all 369 AS568B sizes (as568-parco). Both readings are kept. The 25 sizes are published here because two catalogues carry them with matching dimensions, and each is marked as sitting outside the AS568B list rather than being passed off as a standard size. If you are writing a drawing to AS568B, the 4xx series starts at -425.

The 4xx inside diameters in one catalogue: -446 ID 8.475 in (as568-parco) against -446 ID 8.225 in (as568-oringseal). One catalogue's 4xx block is shifted against the other three from about -446 onward, so its inside diameters there belong to neighbouring dash numbers. The figures printed on this site are the ones the other three agree on. The shift is recorded because it is exactly the kind of error a single-source table hides.

AS568-391 inside diameter tolerance: plus or minus 0.095 in (as568-arc) against plus or minus 0.1 in (as568-parco). No figure is printed. The sources give different tolerances and nothing breaks the tie, so the cell is left empty rather than filled from one chart.