AS568 Size Chart

/AS568 Size Chart
AS568 Size Chart 2019-06-27T11:23:14+00:00

AS568 O-Ring Size Chart

The Global O-Ring and Seal Size Reference Chart covers the AS568 O-Ring Sizes published by the Society of Automotive Engineers (S.A.E.), and includes the Extended Sizes in the 400 Series. The purpose of this chart is to specify the inside diameters, cross-sections, tolerances, and size identification codes (dash numbers) for O-rings used in sealing applications and for straight thread tube fitting boss gaskets. Click here to download a digital copy of our AS568 O-Ring Reference Guide.

Series C/S Inches C/S Frac. C/S mm ID Range
Zero 0.07 1/16 1.78 .029 – 5.239
100 0.103 3/32 2.62 .049 – 9.737
200 0.139 1/8 3.53 .171 – 17.955
300 0.21 3/16 5.33 .412 – 25.940
400 0.275 1/4 6.99 1.350 – 25.940
900 Varies Varies 1.42 – 3.0 .185 – 2.337
request a quote on o-rings
Shop For O-Rings

AS568 O-Ring Size Reference Chart

Dash # CS Nominal ID Nominal OD Nominal CS Inch ID Inch Tol Inch CS mm ID mm Tol mm
001 1/32 1/32 3/32 .040 .029 ± .004 1.02 .74 ± .10
002 3/64 3/64 9/64 .050 .042 ± .004 1.27 1.07 ± .10
003 1/16 1/16 3/16 .060 .056 ± .004 1.52 1.42 ± .10
004 1/16 5/64 13/64 .070 .070 ± .005 1.78 1.78 ± .13
005 1/16 3/32 7/32 .070 .101 ± .005 1.78 2.57 ± .13
006 1/16 1/8 1/4 .070 .114 ± .005 1.78 2.90 ± .13
007 1/16 5/32 9/32 .070 .145 ± .005 1.78 3.68 ± .13
008 1/16 3/16 5/16 .070 .176 ± .005 1.78 4.47 ± .13
009 1/16 7/32 11/32 .070 .208 ± .005 1.78 5.28 ± .13
010 1/16 1/4 3/8 .070 .239 ± .005 1.78 6.07 ± .13
011 1/16 5/16 7/16 .070 .301 ± .005 1.78 7.65 ± .13
012 1/16 3/8 1/2 .070 .364 ± .005 1.78 9.25 ± .13
013 1/16 7/16 9/16 .070 .426 ± .005 1.78 10.82 ± .13
014 1/16 1/2 5/8 .070 .489 ± .005 1.78 12.42 ± .13
015 1/16 9/16 11/16 .070 .551 ± .007 1.78 14.00 ± .18
016 1/16 5/8 3/4 .070 .614 ± .009 1.78 15.60 ± .23
017 1/16 11/16 13/16 .070 .676 ± .009 1.78 17.17 ± .23
018 1/16 3/4 7/8 .070 .739 ± .009 1.78 18.77 ± .23
019 1/16 13/16 15/16 .070 .801 ± .009 1.78 20.35 ± .23
020 1/16 7/8 1 .070 .864 ± .009 1.78 21.95 ± .23
021 1/16 15/16 1-1/16 .070 .926 ± .009 1.78 23.52 ± .23
022 1/16 1 1-1/8 .070 .989 ± .010 1.78 25.12 ± .25
023 1/16 1-1/16 1-3/16 .070 1.051 ± .010 1.78 26.70 ± .25
024 1/16 1-1/8 1-1/4 .070 1.114 ± .010 1.78 28.30 ± .25
025 1/16 1-3/16 1-5/16 .070 1.176 ± .011 1.78 29.87 ± .28
026 1/16 1-1/4 1-3/8 .070 1.239 ± .011 1.78 31.47 ± .28
027 1/16 1-5/16 1-7/16 .070 1.301 ± .011 1.78 33.05 ± .28
028 1/16 1-3/8 1-1/2 .070 1.364 ± .013 1.78 34.65 ± .33
029 1/16 1-1/2 1-5/8 .070 1.489 ± .013 1.78 37.82 ± .33
030 1/16 1-5/8 1-3/4 .070 1.614 ± .013 1.78 41.00 ± .33
031 1/16 1-3/4 1-7/8 .070 1.739 ± .015 1.78 44.17 ± .38
032 1/16 1-7/8 2 .070 1.864 ± .015 1.78 47.35 ± .38
033 1/16 2 2-1/8 .070 1.989 ± .018 1.78 50.52 ± .46
034 1/16 2-1/8 2-1/4 .070 2.114 ± .018 1.78 53.70 ± .46
035 1/16 2-1/4 2-3/8 .070 2.239 ± .018 1.78 56.87 ± .46
036 1/16 2-3/8 2-1/2 .070 2.364 ± .018 1.78 60.05 ± .46
037 1/16 2-1/2 2-5/8 .070 2.489 ± .018 1.78 63.22 ± .46
038 1/16 2-5/8 2-3/4 .070 2.614 ± .020 1.78 66.40 ± .51
039 1/16 2-3/4 2-7/8 .070 2.739 ± .020 1.78 69.57 ± .51
040 1/16 2-7/8 3 .070 2.864 ± .020 1.78 72.75 ± .51
041 1/16 3 3-1/8 .070 2.989 ± .024 1.78 75.92 ± .61
042 1/16 3-1/4 3-3/8 .070 3.239 ± .024 1.78 82.27 ± .61
043 1/16 3-1/2 3-5/8 .070 3.489 ± .024 1.78 88.62 ± .61
044 1/16 3-3/4 3-7/8 .070 3.739 ± .027 1.78 94.97 ± .69
045 1/16 4 4-1/8 .070 3.989 ± .027 1.78 101.32 ± .69
046 1/16 4-1/4 4-3/8 .070 4.239 ± .030 1.78 107.67 ± .76
047 1/16 4-1/2 4-5/8 .070 4.489 ± .030 1.78 114.02 ± .76
048 1/16 4-3/4 4-7/8 .070 4.739 ± .030 1.78 120.37 ± .76
049 1/16 5 5-1/8 .070 4.989 ± .037 1.78 126.72 ± .94
050 1/16 5-1/4 5-3/8 .070 5.239 ± .037 1.78 133.07 ± .94
102 3/32 1/16 1/4 .103 .049 ± .005 2.62 1.24 ± .13
103 3/32 3/32 9/32 .103 .081 ± .005 2.62 2.06 ± .13
104 3/32 1/8 5/16 .103 .112 ± .005 2.62 2.84 ± .13
105 3/32 5/32 11/32 .103 .143 ± .005 2.62 3.63 ± .13
106 3/32 3/16 3/8 .103 .174 ± .005 2.62 4.42 ± .13
107 3/32 7/32 13/32 .103 .206 ± .005 2.62 5.23 ± .13
108 3/32 1/4 7/16 .103 .237 ± .005 2.62 6.02 ± .13
109 3/32 5/16 1/2 .103 .299 ± .005 2.62 7.59 ± .13
110 3/32 3/8 9/16 .103 .362 ± .005 2.62 9.19 ± .13
111 3/32 7/16 5/8 .103 .424 ± .005 2.62 10.77 ± .13
112 3/32 1/2 11/16 .103 .487 ± .005 2.62 12.37 ± .13
113 3/32 9/16 3/4 .103 .549 ± .007 2.62 13.94 ± .18
114 3/32 5/8 13/16 .103 .612 ± .009 2.62 15.54 ± .23
115 3/32 11/16 7/8 .103 .674 ± .009 2.62 17.12 ± .23
116 3/32 3/4 15/16 .103 .737 ± .009 2.62 18.72 ± .23
117 3/32 13/16 1 .103 .799 ± .010 2.62 20.29 ± .25
118 3/32 7/8 1-1/16 .103 .862 ± .010 2.62 21.89 ± .25
119 3/32 15/16 1-1/8 .103 .924 ± .010 2.62 23.47 ± .25
120 3/32 1 1-3/16 .103 .987 ± .010 2.62 25.07 ± .25
121 3/32 1-1/16 1-1/4 .103 1.049 ± .010 2.62 26.64 ± .25
122 3/32 1-1/8 1-5/16 .103 1.112 ± .010 2.62 28.24 ± .25
123 3/32 1-3/16 1-3/8 .103 1.174 ± .012 2.62 29.82 ± .30
124 3/32 1-1/4 1-7/16 .103 1.237 ± .012 2.62 31.42 ± .30
125 3/32 1-5/16 1-1/2 .103 1.299 ± .012 2.62 32.99 ± .30
126 3/32 1-3/8 1-9/16 .103 1.362 ± .012 2.62 34.59 ± .30
127 3/32 1-7/16 1-5/8 .103 1.424 ± .012 2.62 36.17 ± .30
128 3/32 1-1/2 1-11/16 .103 1.487 ± .012 2.62 37.77 ± .30
129 3/32 1-9/16 1-3/4 .103 1.549 ± .015 2.62 39.34 ± .38
130 3/32 1-5/8 1-13/16 .103 1.612 ± .015 2.62 40.94 ± .38
131 3/32 1-11/16 1-7/8 .103 1.674 ± .015 2.62 42.52 ± .38
132 3/32 1-3/4 1-15/16 .103 1.737 ± .015 2.62 44.12 ± .38
133 3/32 1-13/16 2 .103 1.799 ± .015 2.62 45.69 ± .38
134 3/32 1-7/8 2-1/16 .103 1.862 ± .015 2.62 47.29 ± .38
135 3/32 1-15/16 2-1/8 .103 1.925 ± .017 2.62 48.90 ± .43
136 3/32 2 2-3/16 .103 1.987 ± .017 2.62 50.47 ± .43
137 3/32 2-1/16 2-1/4 .103 2.050 ± .017 2.62 52.07 ± .43
138 3/32 2-1/8 2-5/16 .103 2.112 ± .017 2.62 53.64 ± .43
139 3/32 2-3/16 2-3/8 .103 2.175 ± .017 2.62 55.25 ± .43
140 3/32 2-1/4 2-7/16 .103 2.237 ± .017 2.62 56.82 ± .43
141 3/32 2-5/16 2-1/2 .103 2.300 ± .020 2.62 58.42 ± .51
142 3/32 2-3/8 2-9/16 .103 2.362 ± .020 2.62 59.99 ± .51
143 3/32 2-7/16 2-5/8 .103 2.425 ± .020 2.62 61.60 ± .51
144 3/32 2-1/2 2-11/16 .103 2.487 ± .020 2.62 63.17 ± .51
145 3/32 2-9/16 2-3/4 .103 2.550 ± .020 2.62 64.77 ± .51
146 3/32 2-5/8 2-13/16 .103 2.612 ± .020 2.62 66.34 ± .51
147 3/32 2-11/16 2-7/8 .103 2.675 ± .022 2.62 67.95 ± .56
148 3/32 2-3/4 2-15/16 .103 2.737 ± .022 2.62 69.52 ± .56
149 3/32 2-13/16 3 .103 2.800 ± .022 2.62 71.12 ± .56
150 3/32 2-7/8 3-1/16 .103 2.862 ± .022 2.62 72.69 ± .56
151 3/32 3 3-3/16 .103 2.987 ± .024 2.62 75.87 ± .61
152 3/32 3-1/4 3-7/16 .103 3.237 ± .024 2.62 82.22 ± .61
153 3/32 3-1/2 3-11/16 .103 3.487 ± .024 2.62 88.57 ± .61
154 3/32 3-3/4 3-15/16 .103 3.737 ± .028 2.62 94.92 ± .71
155 3/32 4 4-3/16 .103 3.987 ± .028 2.62 101.27 ± .71
156 3/32 4-1/4 4-7/16 .103 4.237 ± .030 2.62 107.62 ± .76
157 3/32 4-1/2 4-11/16 .103 4.487 ± .030 2.62 113.97 ± .76
158 3/32 4-3/4 4-15/16 .103 4.737 ± .030 2.62 120.32 ± .76
159 3/32 5 5-3/16 .103 4.987 ± .035 2.62 126.67 ± .89
160 3/32 5-1/4 5-7/16 .103 5.237 ± .035 2.62 133.02 ± .89
161 3/32 5-1/2 5-11/16 .103 5.487 ± .035 2.62 139.37 ± .89
162 3/32 5-3/4 5-15/16 .103 5.737 ± .035 2.62 145.72 ± .89
163 3/32 6 6-3/16 .103 5.987 ± .035 2.62 152.07 ± .89
164 3/32 6-1/4 6-7/16 .103 6.237 ± .040 2.62 158.42 ± 1.02
165 3/32 6-1/2 6-11/16 .103 6.487 ± .040 2.62 164.77 ± 1.02
166 3/32 6-3/4 6-15/16 .103 6.737 ± .040 2.62 171.12 ± 1.02
167 3/32 7 7-3/16 .103 6.987 ± .040 2.62 177.47 ± 1.02
168 3/32 7-1/4 7-7/16 .103 7.237 ± .045 2.62 183.82 ± 1.14
169 3/32 7-1/2 7-11/16 .103 7.487 ± .045 2.62 190.17 ± 1.14
170 3/32 7-3/4 7-15/16 .103 7.737 ± .045 2.62 196.52 ± 1.14
171 3/32 8 8-3/16 .103 7.987 ± .045 2.62 202.87 ± 1.14
172 3/32 8-1/4 8-7/16 .103 8.237 ± .050 2.62 209.22 ± 1.27
173 3/32 8-1/2 8-11/16 .103 8.487 ± .050 2.62 215.57 ± 1.27
174 3/32 8-3/4 8-15/16 .103 8.737 ± .050 2.62 221.92 ± 1.27
175 3/32 9 9-3/16 .103 8.987 ± .050 2.62 228.27 ± 1.27
176 3/32 9-1/4 9-7/16 .103 9.237 ± .055 2.62 234.62 ± 1.40
177 3/32 9-1/2 9-11/16 .103 9.487 ± .055 2.62 240.97 ± 1.40
178 3/32 9-3/4 9-15/16 .103 9.737 ± .055 2.62 247.32 ± 1.40
201 1/8 3/16 7/16 .139 .171 ± .005 3.53 4.34 ± .13
202 1/8 1/4 1/2 .139 .234 ± .005 3.53 5.94 ± .13
203 1/8 5/16 9/16 .139 .296 ± .005 3.53 7.52 ± .13
204 1/8 3/8 5/8 .139 .359 ± .005 3.53 9.12 ± .13
205 1/8 7/16 11/16 .139 .421 ± .005 3.53 10.69 ± .13
206 1/8 1/2 3/4 .139 .484 ± .005 3.53 12.29 ± .13
207 1/8 9/16 13/16 .139 .546 ± .007 3.53 13.87 ± .18
208 1/8 5/8 7/8 .139 .609 ± .009 3.53 15.47 ± .23
209 1/8 11/16 15/16 .139 .671 ± .009 3.53 17.04 ± .23
210 1/8 3/4 1 .139 .734 ± .010 3.53 18.64 ± .25
211 1/8 13/16 1-1/16 .139 .796 ± .010 3.53 20.22 ± .25
212 1/8 7/8 1-1/8 .139 .859 ± .010 3.53 21.82 ± .25
213 1/8 15/16 1-3/16 .139 .921 ± .010 3.53 23.39 ± .25
214 1/8 1 1-1/4 .139 .984 ± .010 3.53 24.99 ± .25
215 1/8 1-1/16 1-5/16 .139 1.046 ± .010 3.53 26.57 ± .25
216 1/8 1-1/8 1-3/8 .139 1.109 ± .012 3.53 28.17 ± .30
217 1/8 1-3/16 1-7/16 .139 1.171 ± .012 3.53 29.74 ± .30
218 1/8 1-1/4 1-1/2 .139 1.234 ± .012 3.53 31.34 ± .30
219 1/8 1-5/16 1-9/16 .139 1.296 ± .012 3.53 32.92 ± .30
220 1/8 1-3/8 1-5/8 .139 1.359 ± .012 3.53 34.52 ± .30
221 1/8 1-7/16 1-11/16 .139 1.421 ± .012 3.53 36.09 ± .30
222 1/8 1-1/2 1-3/4 .139 1.484 ± .015 3.53 37.69 ± .38
223 1/8 1-5/8 1-7/8 .139 1.609 ± .015 3.53 40.87 ± .38
224 1/8 1-3/4 2 .139 1.734 ± .015 3.53 44.04 ± .38
225 1/8 1-7/8 2-1/8 .139 1.859 ± .018 3.53 47.22 ± .46
226 1/8 2 2-1/4 .139 1.984 ± .018 3.53 50.39 ± .46
227 1/8 2-1/8 2-3/8 .139 2.109 ± .018 3.53 53.57 ± .46
228 1/8 2-1/4 2-1/2 .139 2.234 ± .020 3.53 56.74 ± .51
229 1/8 2-3/8 2-5/8 .139 2.359 ± .020 3.53 59.92 ± .51
230 1/8 2-1/2 2-3/4 .139 2.484 ± .020 3.53 63.09 ± .51
231 1/8 2-5/8 2-7/8 .139 2.609 ± .020 3.53 66.27 ± .51
232 1/8 2-3/4 3 .139 2.734 ± .024 3.53 69.44 ± .61
233 1/8 2-7/8 3-1/8 .139 2.859 ± .024 3.53 72.62 ± .61
234 1/8 3 3-1/4 .139 2.984 ± .024 3.53 75.79 ± .61
235 1/8 3-1/8 3-3/8 .139 3.109 ± .024 3.53 78.97 ± .61
236 1/8 3-1/4 3-1/2 .139 3.234 ± .024 3.53 82.14 ± .61
237 1/8 3-3/8 3-5/8 .139 3.359 ± .024 3.53 85.32 ± .61
238 1/8 3-1/2 3-3/4 .139 3.484 ± .024 3.53 88.49 ± .61
239 1/8 3-5/8 3-7/8 .139 3.609 ± .028 3.53 91.67 ± .71
240 1/8 3-3/4 4 .139 3.734 ± .028 3.53 94.84 ± .71
241 1/8 3-7/8 4-1/8 .139 3.859 ± .028 3.53 98.02 ± .71
242 1/8 4 4-1/4 .139 3.984 ± .028 3.53 101.19 ± .71
243 1/8 4-1/8 4-3/8 .139 4.109 ± .028 3.53 104.37 ± .71
244 1/8 4-1/4 4-1/2 .139 4.234 ± .030 3.53 107.54 ± .76
245 1/8 4-3/8 4-5/8 .139 4.359 ± .030 3.53 110.72 ± .76
246 1/8 4-1/2 4-3/4 .139 4.484 ± .030 3.53 113.89 ± .76
247 1/8 4-5/8 4-7/8 .139 4.609 ± .030 3.53 117.07 ± .76
248 1/8 4-3/4 5 .139 4.734 ± .030 3.53 120.24 ± .76
249 1/8 4-7/8 5-1/8 .139 4.859 ± .035 3.53 123.42 ± .89
250 1/8 5 5-1/4 .139 4.984 ± .035 3.53 126.59 ± .89
251 1/8 5-1/8 5-3/8 .139 5.109 ± .035 3.53 129.77 ± .89
252 1/8 5-1/4 5-1/2 .139 5.234 ± .035 3.53 132.94 ± .89
253 1/8 5-3/8 5-5/8 .139 5.359 ± .035 3.53 136.12 ± .89
254 1/8 5-1/2 5-3/4 .139 5.484 ± .035 3.53 139.29 ± .89
255 1/8 5-5/8 5-7/8 .139 5.609 ± .035 3.53 142.47 ± .89
256 1/8 5-3/4 6 .139 5.734 ± .035 3.53 145.64 ± .89
257 1/8 5-7/8 6-1/8 .139 5.859 ± .035 3.53 148.82 ± .89
258 1/8 6 6-1/4 .139 5.984 ± .035 3.53 151.99 ± .89
259 1/8 6-1/4 6-1/2 .139 6.234 ± .040 3.53 158.34 ± 1.02
260 1/8 6-1/2 6-3/4 .139 6.484 ± .040 3.53 164.69 ± 1.02
261 1/8 6-3/4 7 .139 6.734 ± .040 3.53 171.04 ± 1.02
262 1/8 7 7-1/4 .139 6.984 ± .040 3.53 177.39 ± 1.02
263 1/8 7-1/4 7-1/2 .139 7.234 ± .045 3.53 183.74 ± 1.14
264 1/8 7-1/2 7-3/4 .139 7.484 ± .045 3.53 190.09 ± 1.14
265 1/8 7-3/4 8 .139 7.734 ± .045 3.53 196.44 ± 1.14
266 1/8 8 8-1/4 .139 7.984 ± .045 3.53 202.79 ± 1.14
267 1/8 8-1/4 8-1/2 .139 8.234 ± .050 3.53 209.14 ± 1.27
268 1/8 8-1/2 8-3/4 .139 8.484 ± .050 3.53 215.49 ± 1.27
269 1/8 8-3/4 9 .139 8.734 ± .050 3.53 221.84 ± 1.27
270 1/8 9 9-1/4 .139 8.984 ± .050 3.53 228.19 ± 1.27
271 1/8 9-1/4 9-1/2 .139 9.234 ± .055 3.53 234.54 ± 1.40
272 1/8 9-1/2 9-3/4 .139 9.484 ± .055 3.53 240.89 ± 1.40
273 1/8 9-3/4 10 .139 9.734 ± .055 3.53 247.24 ± 1.40
274 1/8 10 10-1/4 .139 9.984 ± .055 3.53 253.59 ± 1.40
275 1/8 10-1/2 10-3/4 .139 10.484 ± .055 3.53 266.29 ± 1.40
276 1/8 11 11-1/4 .139 10.984 ± .065 3.53 278.99 ± 1.65
277 1/8 11-1/2 11-3/4 .139 11.484 ± .065 3.53 291.69 ± 1.65
278 1/8 12 12-1/4 .139 11.984 ± .065 3.53 304.39 ± 1.65
279 1/8 13 13-1/4 .139 12.984 ± .065 3.53 329.79 ± 1.65
280 1/8 14 14-1/4 .139 13.984 ± .065 3.53 355.19 ± 1.65
281 1/8 15 15-1/4 .139 14.984 ± .065 3.53 380.59 ± 1.65
282 1/8 16 16-1/4 .139 15.955 ± .075 3.53 405.26 ± 1.91
283 1/8 17 17-1/4 .139 16.955 ± .080 3.53 430.66 ± 2.03
284 1/8 18 18-1/4 .139 17.955 ± .085 3.53 456.06 ± 2.16
309 3/16 7/16 13/16 .210 .412 ± .005 5.33 10.46 ± .13
310 3/16 1/2 7/8 .210 .475 ± .005 5.33 12.07 ± .13
311 3/16 9/16 15/16 .210 .537 ± .007 5.33 13.64 ± .18
312 3/16 5/8 1 .210 .600 ± .009 5.33 15.24 ± .23
313 3/16 11/16 1-1/16 .210 .662 ± .009 5.33 16.81 ± .23
314 3/16 3/4 1-1/8 .210 .725 ± .010 5.33 18.42 ± .25
315 3/16 13/16 1-3/16 .210 .787 ± .010 5.33 19.99 ± .25
316 3/16 7/8 1-1/4 .210 .850 ± .010 5.33 21.59 ± .25
317 3/16 15/16 1-5/16 .210 .912 ± .010 5.33 23.16 ± .25
318 3/16 1 1-3/8 .210 .975 ± .010 5.33 24.77 ± .25
319 3/16 1-1/16 1-7/16 .210 1.037 ± .010 5.33 26.34 ± .25
320 3/16 1-1/8 1-1/2 .210 1.100 ± .012 5.33 27.94 ± .30
321 3/16 1-3/16 1-9/16 .210 1.162 ± .012 5.33 29.51 ± .30
322 3/16 1-1/4 1-5/8 .210 1.225 ± .012 5.33 31.12 ± .30
323 3/16 1-5/16 1-11/16 .210 1.287 ± .012 5.33 32.69 ± .30
324 3/16 1-3/8 1-3/4 .210 1.350 ± .012 5.33 34.29 ± .30
325 3/16 1-1/2 1-7/8 .210 1.475 ± .015 5.33 37.47 ± .38
326 3/16 1-5/8 2 .210 1.600 ± .015 5.33 40.64 ± .38
327 3/16 1-3/4 2-1/8 .210 1.725 ± .015 5.33 43.82 ± .38
328 3/16 1-7/8 2-1/4 .210 1.850 ± .015 5.33 46.99 ± .38
329 3/16 2 2-3/8 .210 1.975 ± .018 5.33 50.17 ± .46
330 3/16 2-1/8 2-1/2 .210 2.100 ± .018 5.33 53.34 ± .46
331 3/16 2-1/4 2-5/8 .210 2.225 ± .018 5.33 56.52 ± .46
332 3/16 2-3/8 2-3/4 .210 2.350 ± .018 5.33 59.69 ± .46
333 3/16 2-1/2 2-7/8 .210 2.475 ± .020 5.33 62.87 ± .51
334 3/16 2-5/8 3 .210 2.600 ± .020 5.33 66.04 ± .51
335 3/16 2-3/4 3-1/8 .210 2.725 ± .020 5.33 69.22 ± .51
336 3/16 2-7/8 3-1/4 .210 2.850 ± .020 5.33 72.39 ± .51
337 3/16 3 3-3/8 .210 2.975 ± .024 5.33 75.57 ± .61
338 3/16 3-1/8 3-1/2 .210 3.100 ± .024 5.33 78.74 ± .61
339 3/16 3-1/4 3-5/8 .210 3.225 ± .024 5.33 81.92 ± .61
340 3/16 3-3/8 3-3/4 .210 3.350 ± .024 5.33 85.09 ± .61
341 3/16 3-1/2 3-7/8 .210 3.475 ± .024 5.33 88.27 ± .61
342 3/16 3-5/8 4 .210 3.600 ± .028 5.33 91.44 ± .71
343 3/16 3-3/4 4-1/8 .210 3.725 ± .028 5.33 94.62 ± .71
344 3/16 3-7/8 4-1/4 .210 3.850 ± .028 5.33 97.79 ± .71
345 3/16 4 4-3/8 .210 3.975 ± .028 5.33 100.97 ± .71
346 3/16 4-1/8 4-1/2 .210 4.100 ± .028 5.33 104.14 ± .71
347 3/16 4-1/4 4-5/8 .210 4.225 ± .030 5.33 107.32 ± .76
348 3/16 4-3/8 4-3/4 .210 4.350 ± .030 5.33 110.49 ± .76
349 3/16 4-1/2 4-7/8 .210 4.475 ± .030 5.33 113.67 ± .76
350 3/16 4-5/8 5 .210 4.600 ± .030 5.33 116.84 ± .76
351 3/16 4-3/4 5-1/8 .210 4.725 ± .030 5.33 120.02 ± .76
352 3/16 4-7/8 5-1/4 .210 4.850 ± .030 5.33 123.19 ± .76
353 3/16 5 5-3/8 .210 4.975 ± .037 5.33 126.37 ± .94
354 3/16 5-1/8 5-1/2 .210 5.100 ± .037 5.33 129.54 ± .94
355 3/16 5-1/4 5-5/8 .210 5.225 ± .037 5.33 132.72 ± .94
356 3/16 5-3/8 5-3/4 .210 5.350 ± .037 5.33 135.89 ± .94
357 3/16 5-1/2 5-7/8 .210 5.475 ± .037 5.33 139.07 ± .94
358 3/16 5-5/8 6 .210 5.600 ± .037 5.33 142.24 ± .94
359 3/16 5-3/4 6-1/8 .210 5.725 ± .037 5.33 145.42 ± .94
360 3/16 5-7/8 6-1/4 .210 5.850 ± .037 5.33 148.59 ± .94
361 3/16 6 6-3/8 .210 5.975 ± .037 5.33 151.77 ± .94
362 3/16 6-1/4 6-5/8 .210 6.225 ± .040 5.33 158.12 ± 1.02
363 3/16 6-1/2 6-7/8 .210 6.475 ± .040 5.33 164.47 ± 1.02
364 3/16 6-3/4 7-1/8 .210 6.725 ± .040 5.33 170.82 ± 1.02
365 3/16 7 7-3/8 .210 6.975 ± .040 5.33 177.17 ± 1.02
366 3/16 7-1/4 7-5/8 .210 7.225 ± .045 5.33 183.52 ± 1.14
367 3/16 7-1/2 7-7/8 .210 7.475 ± .045 5.33 189.87 ± 1.14
368 3/16 7-3/4 8-1/8 .210 7.725 ± .045 5.33 196.22 ± 1.14
369 3/16 8 8-3/8 .210 7.975 ± .045 5.33 202.57 ± 1.14
370 3/16 8-1/4 8-5/8 .210 8.225 ± .050 5.33 208.92 ± 1.27
371 3/16 8-1/2 8-7/8 .210 8.475 ± .050 5.33 215.27 ± 1.27
372 3/16 8-3/4 9-1/8 .210 8.725 ± .050 5.33 221.62 ± 1.27
373 3/16 9 9-3/8 .210 8.975 ± .050 5.33 227.97 ± 1.27
374 3/16 9-1/4 9-5/8 .210 9.225 ± .055 5.33 234.32 ± 1.40
375 3/16 9-1/2 9-7/8 .210 9.475 ± .055 5.33 240.67 ± 1.40
376 3/16 9-3/4 10-1/8 .210 9.725 ± .055 5.33 247.02 ± 1.40
377 3/16 10 10-3/8 .210 9.975 ± .055 5.33 253.37 ± 1.40
378 3/16 10-1/2 10-7/8 .210 10.475 ± .060 5.33 266.07 ± 1.52
379 3/16 11 11-3/8 .210 10.975 ± .060 5.33 278.77 ± 1.52
380 3/16 11-1/2 11-7/8 .210 11.475 ± .065 5.33 291.47 ± 1.65
381 3/16 12 12-3/8 .210 11.975 ± .065 5.33 304.17 ± 1.65
382 3/16 13 13-3/8 .210 12.975 ± .065 5.33 329.57 ± 1.65
383 3/16 14 14-3/8 .210 13.975 ± .070 5.33 354.97 ± 1.78
384 3/16 15 15-3/8 .210 14.975 ± .070 5.33 380.37 ± 1.78
385 3/16 16 16-3/8 .210 15.955 ± .075 5.33 405.26 ± 1.91
386 3/16 17 17-3/8 .210 16.955 ± .080 5.33 430.66 ± 2.03
387 3/16 18 18-3/8 .210 17.955 ± .085 5.33 456.06 ± 2.16
388 3/16 19 19-3/8 .210 18.955 ± .090 5.33 481.46 ± 2.29
389 3/16 20 20-3/8 .210 19.955 ± .095 5.33 506.86 ± 2.41
390 3/16 21 21-3/8 .210 20.955 ± .095 5.33 532.26 ± 2.41
391 3/16 22 22-3/8 .210 21.955 ± .095 5.33 557.66 ± 2.41
392 3/16 23 23-3/8 .210 22.940 ± .105 5.33 582.68 ± 2.67
393 3/16 24 24-3/8 .210 23.940 ± .110 5.33 608.08 ± 2.79
394 3/16 25 25-3/8 .210 24.940 ± .115 5.33 633.48 ± 2.92
395 3/16 26 26-3/8 .210 25.940 ± .120 5.33 658.88 ± 3.05
400 1/4 1-3/8 1-7/8 .275 1.350 ± .012 6.99 34.29 ± .30
401 1/4 1-1/2 2 .275 1.475 ± .015 6.99 37.47 ± .38
402 1/4 1-5/8 2-1/8 .275 1.600 ± .015 6.99 40.64 ± .38
403 1/4 1-3/4 2-1/4 .275 1.725 ± .015 6.99 43.82 ± .38
404 1/4 1-7/8 2-3/8 .275 1.850 ± .015 6.99 46.99 ± .38
405 1/4 2 2-1/2 .275 1.975 ± .018 6.99 50.17 ± .46
406 1/4 2-1/8 2-5/8 .275 2.100 ± .018 6.99 53.34 ± .46
407 1/4 2-1/4 2-3/4 .275 2.225 ± .018 6.99 56.52 ± .46
408 1/4 2-3/8 2-7/8 .275 2.350 ± .018 6.99 59.69 ± .46
409 1/4 2-1/2 3 .275 2.475 ± .020 6.99 62.87 ± .51
410 1/4 2-5/8 3-1/8 .275 2.600 ± .020 6.99 66.04 ± .51
411 1/4 2-3/4 3-1/4 .275 2.725 ± .020 6.99 69.22 ± .51
412 1/4 2-7/8 3-3/8 .275 2.850 ± .020 6.99 72.39 ± .51
413 1/4 3 3-1/2 .275 2.975 ± .024 6.99 75.57 ± .61
414 1/4 3-1/8 3-5/8 .275 3.100 ± .024 6.99 78.74 ± .61
415 1/4 3-1/4 3-3/4 .275 3.225 ± .024 6.99 81.92 ± .61
416 1/4 3-3/8 3-7/8 .275 3.350 ± .024 6.99 85.09 ± .61
417 1/4 3-1/2 4 .275 3.475 ± .024 6.99 88.27 ± .61
418 1/4 3-5/8 4-1/8 .275 3.600 ± .028 6.99 91.44 ± .71
419 1/4 3-3/4 4-1/4 .275 3.725 ± .028 6.99 94.62 ± .71
420 1/4 3-7/8 4-3/8 .275 3.850 ± .028 6.99 97.79 ± .71
421 1/4 4 4-1/2 .275 3.975 ± .028 6.99 100.97 ± .71
422 1/4 4-1/8 4-5/8 .275 4.100 ± .028 6.99 104.14 ± .71
423 1/4 4-1/4 4-3/4 .275 4.225 ± .030 6.99 107.32 ± .76
424 1/4 4-3/8 4-7/8 .275 4.350 ± .030 6.99 110.49 ± .76
425 1/4 4-1/2 5 .275 4.475 ± .033 6.99 113.67 ± .84
426 1/4 4-5/8 5-1/8 .275 4.600 ± .033 6.99 116.84 ± .84
427 1/4 4-3/4 5-1/4 .275 4.725 ± .033 6.99 120.02 ± .84
428 1/4 4-7/8 5-3/8 .275 4.850 ± .033 6.99 123.19 ± .84
429 1/4 5 5-1/2 .275 4.975 ± .037 6.99 126.37 ± .94
430 1/4 5-1/8 5-5/8 .275 5.100 ± .037 6.99 129.54 ± .94
431 1/4 5-1/4 5-3/4 .275 5.225 ± .037 6.99 132.72 ± .94
432 1/4 5-3/8 5-7/8 .275 5.350 ± .037 6.99 135.89 ± .94
433 1/4 5-1/2 6 .275 5.475 ± .037 6.99 139.07 ± .94
434 1/4 5-5/8 6-1/8 .275 5.600 ± .037 6.99 142.24 ± .94
435 1/4 5-3/4 6-1/4 .275 5.725 ± .037 6.99 145.42 ± .94
436 1/4 5-7/8 6-3/8 .275 5.850 ± .037 6.99 148.59 ± .94
437 1/4 6 6-1/2 .275 5.975 ± .037 6.99 151.77 ± .94
438 1/4 6-1/4 6-3/4 .275 6.225 ± .040 6.99 158.12 ± 1.02
439 1/4 6-1/2 7 .275 6.475 ± .040 6.99 164.47 ± 1.02
440 1/4 6-3/4 7-1/4 .275 6.725 ± .040 6.99 170.82 ± 1.02
441 1/4 7 7-1/2 .275 6.975 ± .040 6.99 177.17 ± 1.02
442 1/4 7-1/4 7-3/4 .275 7.225 ± .045 6.99 183.52 ± 1.14
443 1/4 7-1/2 8 .275 7.475 ± .045 6.99 189.87 ± 1.14
444 1/4 7-3/4 8-1/4 .275 7.725 ± .045 6.99 196.22 ± 1.14
445 1/4 8 8-1/2 .275 7.975 ± .045 6.99 202.57 ± 1.14
446 1/4 8-1/2 9 .275 8.475 ± .055 6.99 215.27 ± 1.40
447 1/4 9 9-1/2 .275 8.975 ± .055 6.99 227.97 ± 1.40
448 1/4 9-1/2 10 .275 9.475 ± .055 6.99 240.67 ± 1.40
449 1/4 10 10-1/2 .275 9.975 ± .055 6.99 253.37 ± 1.40
450 1/4 10-1/2 11 .275 10.475 ± .060 6.99 266.07 ± 1.52
451 1/4 11 11-1/2 .275 10.975 ± .060 6.99 278.77 ± 1.52
452 1/4 11-1/2 12 .275 11.475 ± .060 6.99 291.47 ± 1.52
453 1/4 12 12-1/2 .275 11.975 ± .060 6.99 304.17 ± 1.52
454 1/4 12-1/2 13 .275 12.475 ± .060 6.99 316.87 ± 1.52
455 1/4 13 13-1/2 .275 12.975 ± .060 6.99 329.57 ± 1.52
456 1/4 13-1/2 14 .275 13.475 ± .070 6.99 342.27 ± 1.78
457 1/4 14 14-1/2 .275 13.975 ± .070 6.99 354.97 ± 1.78
458 1/4 14-1/2 15 .275 14.475 ± .070 6.99 367.67 ± 1.78
459 1/4 15 15-1/2 .275 14.975 ± .070 6.99 380.37 ± 1.78
460 1/4 15-1/2 16 .275 15.475 ± .070 6.99 393.07 ± 1.78
461 1/4 16 16-1/2 .275 15.955 ± .075 6.99 405.26 ± 1.91
462 1/4 16-1/2 17 .275 16.455 ± .075 6.99 417.96 ± 1.91
463 1/4 17 17-1/2 .275 16.955 ± .080 6.99 430.66 ± 2.03
464 1/4 17-1/2 18 .275 17.455 ± .085 6.99 443.36 ± 2.16
465 1/4 18 18-1/2 .275 17.955 ± .085 6.99 456.06 ± 2.16
466 1/4 18-1/2 19 .275 18.455 ± .085 6.99 468.76 ± 2.16
467 1/4 19 19-1/2 .275 18.955 ± .090 6.99 481.46 ± 2.29
468 1/4 19-1/2 20 .275 19.455 ± .090 6.99 494.16 ± 2.29
469 1/4 20 20-1/2 .275 19.955 ± .095 6.99 506.86 ± 2.41
470 1/4 21 21-1/2 .275 20.955 ± .095 6.99 532.26 ± 2.41
471 1/4 22 22-1/2 .275 21.955 ± .100 6.99 557.66 ± 2.54
472 1/4 23 23-1/2 .275 22.940 ± .105 6.99 582.68 ± 2.67
473 1/4 24 24-1/2 .275 23.940 ± .110 6.99 608.08 ± 2.79
474 1/4 25 25-1/2 .275 24.940 ± .115 6.99 633.48 ± 2.92
475 1/4 26 26-1/2 .275 25.940 ± .120 6.99 658.88 ± 3.05
901 .056 .185 ± .005 1.42 4.70 ± .13
902 .064 .239 ± .005 1.63 6.07 ± .13
903 .064 .301 ± .005 1.63 7.65 ± .13
904 .072 .351 ± .005 1.83 8.92 ± .13
905 .072 .414 ± .005 1.83 10.52 ± .13
906 .078 .468 ± .005 1.98 11.89 ± .13
907 .082 .530 ± .007 2.08 13.46 ± .18
908 .087 .644 ± .009 2.21 16.36 ± .23
909 .097 .706 ± .009 2.46 17.93 ± .23
910 .097 .755 ± .009 2.46 19.18 ± .23
911 .116 .863 ± .009 2.95 21.92 ± .23
912 .116 .924 ± .009 2.95 23.47 ± .23
913 .116 .986 ± .010 2.95 25.04 ± .25
914 .116 1.047 ± .010 2.95 26.59 ± .25
916 .116 1.171 ± .010 2.95 29.74 ± .25
918 .116 1.355 ± .012 2.95 34.42 ± .30
920 .118 1.475 ± .014 3.00 37.47 ± .36
924 .118 1.720 ± .014 3.00 43.69 ± .36
928 .118 2.090 ± .018 3.00 53.09 ± .46
932 .118 2.337 ± .018 3.00 59.36 ± .46

History

This size chart was first published in 1971 by the A-6c2 Seals Committee at SAE (Society of Automotive Engineers) as Aerospace Standard AS568. These standards were later republished in 1974 as AS568A, in 2001 as AS568B, and most recently in 2008 as AS568C. Any of these terms (AS568, AS568A, AS568B, AS568C) may be used interchangeably when referring to an o-ring dash size.

Actual vs. Nominal

To assist our customers in selecting the correct size o-ring we have included 3 measurements for cross reference purposes; the “Nominal”, “Actual Inch”, and “Actual Metric” sizes. We are often asked “What is the difference between Actual and Nominal sizes for o-rings?”. The Nominal (fractional) dimensions are in name only (often used when verbally describing the size). For more accurate measurements, please refer to the actual inch or millimeter sizes, as these are the true dimensions of the o-ring.

O-Ring Formulas:

To calculate an o-ring’s outside diameter (OD) you may use this formula: 2(CS) + ID = OD
Conversely, if you have the OD and need to find the ID use this formula: OD – 2(CS) = ID