The original product and technical standard for metric o-rings was DIN 3771. In 2010, the ISO 3601 standards replaced DIN 3771 and became the latest implementation standard for metric o-rings. They are issued and approved by the SC7 Sealing Devices Subcommittee of the ISO/TC131 Technical Committee on Fluid Power Systems. China’s national standard, the GB/T 3452 series of standards, is equivalent to the ISO 3601 standard.
Savvy is a leading China o-ring manufacturer with many standard molds (tools) and a large stock of metric o-rings. Combined with our Material Spec Sheet, Hardness Spec Sheet, and Groove Size Chart, you can quickly select and find the best metric o-rings for your equipment use from the following ISO 3601 O-Ring Size Chart. If not found, we can also manufacture custom metric o-rings, like most miniature metric o-rings (CS 0.5mm), for you quickly.
ISO 3601-1: Dimensional Tolerances
ISO 3601-1 specifies the inside diameters, cross-sections, tolerances, and designation codes for imperial and metric o-rings used in fluid power systems for general industrial and aerospace applications. The dimensions and tolerances specified in ISO 3601-1 are suitable for any elastomeric material, e.g., NBR, HNBR, Silicone, EPDM, FKM, FFKM, FVMQ, PU, PTFE, etc., provided that suitable tooling is available.o
ISO 3601-3: Quality Acceptance Criteria
ISO 3601-3 lays down the quality acceptance criteria for o-rings used in fluid systems. It also defines and classifies surface imperfections on o-rings and specifies maximum acceptable limits for these imperfections. This part is also applicable to o-rings used in aerospace construction. There are three grades (N, S, CS) for defects identification on the sides of appearance, surface, and flash.
Grade N (general purpose) identifies acceptance criteria for O-rings intended for general use.
Grade S (special) identifies acceptance criteria for O-rings intended for applications requiring a higher level of quality and/or precision with respect to dimensional tolerances of surface imperfections. For example, aerospace, critical industrial, or automotive applications are covered by this grade.
Grade CS (critical service) identifies acceptance criteria for O-rings intended for applications requiring a much higher level of quality and/or precision with respect to dimensional tolerances of surface imperfections. For example, critical service aerospace or medical applications, where the surface of the O-ring must be near-perfect to perform in a satisfactory manner, are covered by this grade.
ISO 3601 O-Ring Size Chart
The ISO 3601 O-Ring Size Chart is divided into two parts: Class A and Class B. Class A corresponds to the current format of the American standard AS568 (excluding dash 900 series). Class B is divided into four groups (A-E), all of which are international standard metric o-rings, and these sizes are commonly used worldwide. The table specifies the ID (inside diameter), CS (cross section), and reference size identification code (Ref.) for all standard metric o-rings.
INTERNATIONAL STANDARD ISO 3601 O-RING SIZE CHART BY REFERNCES & DIMENSIONS
| Group A | ||
|---|---|---|
| Ref. | ID (mm) | CS (mm) |
| A0018 | 1.80 | 1.80 |
| A0020 | 2.00 | 1.80 |
| A0024 | 2.24 | 1.80 |
| A0025 | 2.50 | 1.80 |
| A0028 | 2.80 | 1.80 |
| A0032 | 3.15 | 1.80 |
| A0036 | 3.55 | 1.80 |
| A0038 | 3.75 | 1.80 |
| A0040 | 4.00 | 1.80 |
| A0045 | 4.50 | 1.80 |
| A0049 | 4.87 | 1.80 |
| A0050 | 5.00 | 1.80 |
| A0052 | 5.15 | 1.80 |
| A0053 | 5.30 | 1.80 |
| A0056 | 5.60 | 1.80 |
| A0060 | 6.00 | 1.80 |
| A0063 | 6.30 | 1.80 |
| A0067 | 6.70 | 1.80 |
| A0079 | 6.90 | 1.80 |
| A0071 | 7.10 | 1.80 |
| A0075 | 7.50 | 1.80 |
| A0080 | 8.00 | 1.80 |
| A0085 | 8.50 | 1.80 |
| A0088 | 8.75 | 1.80 |
| A0090 | 9.00 | 1.80 |
| A0095 | 9.50 | 1.80 |
| A0100 | 10.00 | 1.80 |
| A0106 | 10.60 | 1.80 |
| A0112 | 11.20 | 1.80 |
| A0118 | 11.80 | 1.80 |
| A0125 | 12.50 | 1.80 |
| A0132 | 13.20 | 1.80 |
| A0140 | 14.00 | 1.80 |
| A0150 | 15.00 | 1.80 |
| A0160 | 16.00 | 1.80 |
| A0170 | 17.00 | 1.80 |
| A0180 | 18.00 | 1.80 |
| A0190 | 19.00 | 1.80 |
| A0200 | 20.00 | 1.80 |
| A0212 | 21.20 | 1.80 |
| A0224 | 22.40 | 1.80 |
| A0236 | 23.60 | 1.80 |
| A0250 | 25.00 | 1.80 |
| A0258 | 25.80 | 1.80 |
| A0265 | 26.50 | 1.80 |
| A0280 | 28.00 | 1.80 |
| A0300 | 30.00 | 1.80 |
| A0315 | 31.50 | 1.80 |
| A0325 | 32.50 | 1.80 |
| A0335 | 33.50 | 1.80 |
| A0345 | 34.50 | 1.80 |
| A0355 | 35.50 | 1.80 |
| A0365 | 36.50 | 1.80 |
| A0375 | 37.50 | 1.80 |
| A0380 | 38.70 | 1.80 |
| A0400 | 40.00 | 1.80 |
| A0412 | 41.20 | 1.80 |
| A0425 | 42.50 | 1.80 |
| A0437 | 43.70 | 1.80 |
| A0450 | 45.00 | 1.80 |
| A0475 | 47.50 | 1.80 |
| A0500 | 50.00 | 1.80 |
| A0530 | 53.00 | 1.80 |
| A0560 | 56.00 | 1.80 |
| A0600 | 60.00 | 1.80 |
| A0630 | 63.00 | 1.80 |
| A0670 | 67.00 | 1.80 |
| A0710 | 71.00 | 1.80 |
| A0750 | 75.00 | 1.80 |
| A0800 | 80.00 | 1.80 |
| A0850 | 85.00 | 1.80 |
| A0900 | 90.00 | 1.80 |
| A0950 | 95.00 | 1.80 |
| A1000 | 100.00 | 1.80 |
| A1060 | 106.00 | 1.80 |
| A1120 | 112.00 | 1.80 |
| A1180 | 118.00 | 1.80 |
| A1250 | 125.00 | 1.80 |
| Group B | ||
|---|---|---|
| Ref. | ID (mm) | CS (mm) |
| B0045 | 4.50 | 2.65 |
| B0053 | 5.30 | 2.65 |
| B0060 | 6.00 | 2.65 |
| B0069 | 6.90 | 2.65 |
| B0080 | 8.00 | 2.65 |
| B0090 | 9.00 | 2.65 |
| B0095 | 9.50 | 2.65 |
| B0100 | 10.00 | 2.65 |
| B0106 | 10.60 | 2.65 |
| B0112 | 11.20 | 2.65 |
| B0118 | 11.80 | 2.65 |
| B0125 | 12.50 | 2.65 |
| B0132 | 13.20 | 2.65 |
| B0140 | 14.00 | 2.65 |
| B0150 | 15.00 | 2.65 |
| B0160 | 16.00 | 2.65 |
| B0170 | 17.00 | 2.65 |
| B0180 | 18.00 | 2.65 |
| B0190 | 19.00 | 2.65 |
| B0200 | 20.00 | 2.65 |
| B0212 | 21.20 | 2.65 |
| B0224 | 22.40 | 2.65 |
| B0236 | 23.60 | 2.65 |
| B0250 | 25.00 | 2.65 |
| B0258 | 25.80 | 2.65 |
| B0265 | 26.50 | 2.65 |
| B0280 | 28.00 | 2.65 |
| B0300 | 30.00 | 2.65 |
| B0315 | 31.50 | 2.65 |
| B0325 | 32.50 | 2.65 |
| B0335 | 33.50 | 2.65 |
| B0345 | 34.50 | 2.65 |
| B0355 | 35.50 | 2.65 |
| B0365 | 36.50 | 2.65 |
| B0375 | 37.50 | 2.65 |
| B0387 | 38.70 | 2.65 |
| B0400 | 40.00 | 2.65 |
| B0412 | 41.20 | 2.65 |
| B0425 | 42.50 | 2.65 |
| B0437 | 43.70 | 2.65 |
| B0450 | 45.00 | 2.65 |
| B0462 | 46.20 | 2.65 |
| B0475 | 47.50 | 2.65 |
| B0487 | 48.70 | 2.65 |
| B0500 | 50.00 | 2.65 |
| B0515 | 51.50 | 2.65 |
| B0530 | 53.00 | 2.65 |
| B0545 | 54.50 | 2.65 |
| B0560 | 56.00 | 2.65 |
| B0580 | 58.00 | 2.65 |
| B0600 | 60.00 | 2.65 |
| B0615 | 61.50 | 2.65 |
| B0630 | 63.00 | 2.65 |
| B0650 | 65.00 | 2.65 |
| B0670 | 67.00 | 2.65 |
| B0690 | 69.00 | 2.65 |
| B0710 | 71.00 | 2.65 |
| B0730 | 73.00 | 2.65 |
| B0750 | 75.00 | 2.65 |
| B0800 | 80.00 | 2.65 |
| B0850 | 85.00 | 2.65 |
| B0900 | 90.00 | 2.65 |
| B0950 | 95.00 | 2.65 |
| B1000 | 100.00 | 2.65 |
| B1060 | 106.00 | 2.65 |
| B1120 | 112.00 | 2.65 |
| B1180 | 118.00 | 2.65 |
| B1250 | 125.00 | 2.65 |
| B1320 | 132.00 | 2.65 |
| B1400 | 140.00 | 2.65 |
| B1500 | 150.00 | 2.65 |
| B1600 | 160.00 | 2.65 |
| B1700 | 170.00 | 2.65 |
| B1800 | 180.00 | 2.65 |
| B1900 | 190.00 | 2.65 |
| B2000 | 200.00 | 2.65 |
| B2120 | 212.00 | 2.65 |
| B2240 | 224.00 | 2.65 |
| B2300 | 230.00 | 2.65 |
| B2360 | 236.00 | 2.65 |
| B2430 | 243.00 | 2.65 |
| B2500 | 250.00 | 2.65 |
| Group C | ||
|---|---|---|
| Ref. | ID (mm) | CS (mm) |
| C0140 | 14.00 | 3.55 |
| C0150 | 15.00 | 3.55 |
| C0160 | 16.00 | 3.55 |
| C0170 | 17.00 | 3.55 |
| C0180 | 18.00 | 3.55 |
| C0190 | 19.00 | 3.55 |
| C0200 | 20.00 | 3.55 |
| C0212 | 21.20 | 3.55 |
| C0224 | 22.40 | 3.55 |
| C0236 | 23.60 | 3.55 |
| C0250 | 25.00 | 3.55 |
| C0258 | 25.80 | 3.55 |
| C0265 | 26.50 | 3.55 |
| C0280 | 28.00 | 3.55 |
| C0300 | 30.00 | 3.55 |
| C0315 | 31.50 | 3.55 |
| C0325 | 32.50 | 3.55 |
| C0335 | 33.50 | 3.55 |
| C0345 | 34.50 | 3.55 |
| C0355 | 35.50 | 3.55 |
| C0365 | 36.50 | 3.55 |
| C0375 | 37.50 | 3.55 |
| C0387 | 38.70 | 3.55 |
| C0400 | 40.00 | 3.55 |
| C0412 | 41.20 | 3.55 |
| C0425 | 42.50 | 3.55 |
| C0437 | 43.70 | 3.55 |
| C0450 | 45.00 | 3.55 |
| C0462 | 46.20 | 3.55 |
| C0475 | 47.50 | 3.55 |
| C0487 | 48.70 | 3.55 |
| C0500 | 50.00 | 3.55 |
| C0515 | 51.50 | 3.55 |
| C0530 | 53.00 | 3.55 |
| C0545 | 54.50 | 3.55 |
| C0560 | 56.00 | 3.55 |
| C0580 | 58.00 | 3.55 |
| C0600 | 60.00 | 3.55 |
| C0615 | 61.50 | 3.55 |
| C0630 | 63.00 | 3.55 |
| C0650 | 65.00 | 3.55 |
| C0670 | 67.00 | 3.55 |
| C0690 | 69.00 | 3.55 |
| C0710 | 71.00 | 3.55 |
| C0730 | 73.00 | 3.55 |
| C0750 | 75.00 | 3.55 |
| C0775 | 77.00 | 3.55 |
| C0800 | 80.00 | 3.55 |
| C0825 | 82.50 | 3.55 |
| C0850 | 85.00 | 3.55 |
| C0875 | 87.50 | 3.55 |
| C0900 | 90.00 | 3.55 |
| C0925 | 92.50 | 3.55 |
| C0950 | 95.00 | 3.55 |
| C0975 | 97.50 | 3.55 |
| C1000 | 100.00 | 3.55 |
| C1030 | 103.00 | 3.55 |
| C1060 | 106.00 | 3.55 |
| C1090 | 109.00 | 3.55 |
| C1120 | 112.00 | 3.55 |
| C1150 | 115.00 | 3.55 |
| C1180 | 118.00 | 3.55 |
| C1220 | 122.00 | 3.55 |
| C1250 | 125.00 | 3.55 |
| C1280 | 128.00 | 3.55 |
| C1320 | 132.00 | 3.55 |
| C1360 | 136.00 | 3.55 |
| C1400 | 140.00 | 3.55 |
| C1450 | 145.00 | 3.55 |
| C1500 | 150.00 | 3.55 |
| C1550 | 155.00 | 3.55 |
| C1600 | 160.00 | 3.55 |
| C1650 | 165.00 | 3.55 |
| C1700 | 170.00 | 3.55 |
| C1750 | 175.00 | 3.55 |
| C1800 | 180.00 | 3.55 |
| C1850 | 185.00 | 3.55 |
| C1900 | 190.00 | 3.55 |
| C1950 | 195.00 | 3.55 |
| C2000 | 200.00 | 3.55 |
| C2120 | 212.00 | 3.55 |
| C2180 | 218.00 | 3.55 |
| C2240 | 224.00 | 3.55 |
| C2300 | 230.00 | 3.55 |
| C2360 | 236.00 | 3.55 |
| C2500 | 250.00 | 3.55 |
| C2580 | 258.00 | 3.55 |
| C2650 | 265.00 | 3.55 |
| C2800 | 280.00 | 3.55 |
| C2900 | 290.00 | 3.55 |
| C3000 | 300.00 | 3.55 |
| C3070 | 307.00 | 3.55 |
| C3150 | 315.00 | 3.55 |
| C3350 | 335.00 | 3.55 |
| C3550 | 355.00 | 3.55 |
| Group D | ||
|---|---|---|
| Ref. | ID (mm) | CS (mm) |
| D0375 | 37.50 | 5.30 |
| D0387 | 38.70 | 5.30 |
| D0400 | 40.00 | 5.30 |
| D0412 | 41.20 | 5.30 |
| D0425 | 42.50 | 5.30 |
| D0437 | 43.70 | 5.30 |
| D0450 | 45.00 | 5.30 |
| D0462 | 46.20 | 5.30 |
| D0475 | 47.50 | 5.30 |
| D0487 | 48.70 | 5.30 |
| D0500 | 50.00 | 5.30 |
| D0515 | 51.50 | 5.30 |
| D0530 | 53.00 | 5.30 |
| D0545 | 54.50 | 5.30 |
| D0560 | 56.00 | 5.30 |
| D0580 | 58.00 | 5.30 |
| D0600 | 60.00 | 5.30 |
| D0615 | 61.50 | 5.30 |
| D0630 | 63.00 | 5.30 |
| D0650 | 65.00 | 5.30 |
| D0670 | 67.00 | 5.30 |
| D0690 | 69.00 | 5.30 |
| D0710 | 71.00 | 5.30 |
| D0730 | 73.00 | 5.30 |
| D0750 | 75.00 | 5.30 |
| D0775 | 77.50 | 5.30 |
| D0800 | 80.00 | 5.30 |
| D0825 | 82.50 | 5.30 |
| D0850 | 85.00 | 5.30 |
| D0875 | 87.50 | 5.30 |
| D0900 | 90.00 | 5.30 |
| D0925 | 92.50 | 5.30 |
| D0950 | 95.00 | 5.30 |
| D0975 | 97.50 | 5.30 |
| D1000 | 100.00 | 5.30 |
| D1030 | 103.00 | 5.30 |
| D1060 | 106.00 | 5.30 |
| D1090 | 109.00 | 5.30 |
| D1120 | 112.00 | 5.30 |
| D1150 | 115.00 | 5.30 |
| D1180 | 118.00 | 5.30 |
| D1220 | 122.00 | 5.30 |
| D1250 | 125.00 | 5.30 |
| D1280 | 128.00 | 5.30 |
| D1320 | 132.00 | 5.30 |
| D1360 | 136.00 | 5.30 |
| D1400 | 140.00 | 5.30 |
| D1450 | 145.00 | 5.30 |
| D1500 | 150.00 | 5.30 |
| D1550 | 155.00 | 5.30 |
| D1600 | 160.00 | 5.30 |
| D1650 | 165.00 | 5.30 |
| D1700 | 170.00 | 5.30 |
| D1750 | 175.00 | 5.30 |
| D1800 | 180.00 | 5.30 |
| D1850 | 185.00 | 5.30 |
| D1900 | 190.00 | 5.30 |
| D1950 | 195.00 | 5.30 |
| D2000 | 200.00 | 5.30 |
| Group E | ||
|---|---|---|
| Ref. | ID (mm) | CS (mm) |
| E1090 | 109.00 | 7.00 |
| E1120 | 112.00 | 7.00 |
| E1150 | 115.00 | 7.00 |
| E1180 | 118.00 | 7.00 |
| E1220 | 122.00 | 7.00 |
| E1250 | 125.00 | 7.00 |
| E1280 | 128.00 | 7.00 |
| E1320 | 132.00 | 7.00 |
| E1360 | 136.00 | 7.00 |
| E1400 | 140.00 | 7.00 |
| E1450 | 145.00 | 7.00 |
| E1500 | 150.00 | 7.00 |
| E1550 | 155.00 | 7.00 |
| E1600 | 160.00 | 7.00 |
| E1650 | 165.00 | 7.00 |
| E1700 | 170.00 | 7.00 |
| E1750 | 175.00 | 7.00 |
| E1800 | 180.00 | 7.00 |
| E1850 | 185.00 | 7.00 |
| E1900 | 190.00 | 7.00 |
| E1950 | 195.00 | 7.00 |
| E2000 | 200.00 | 7.00 |
| E2060 | 206.00 | 7.00 |
| E2120 | 212.00 | 7.00 |
| E2180 | 218.00 | 7.00 |
| E2240 | 224.00 | 7.00 |
| E2300 | 230.00 | 7.00 |
| E2360 | 236.00 | 7.00 |
| E2430 | 243.00 | 7.00 |
| E2500 | 250.00 | 7.00 |
| E2580 | 258.00 | 7.00 |
| E2650 | 265.00 | 7.00 |
| E2720 | 272.00 | 7.00 |
| E2800 | 280.00 | 7.00 |
| E2900 | 290.00 | 7.00 |
| E3000 | 300.00 | 7.00 |
| E3070 | 307.00 | 7.00 |
| E3150 | 315.00 | 7.00 |
| E3250 | 325.00 | 7.00 |
| E3350 | 335.00 | 7.00 |
| E3450 | 345.00 | 7.00 |
| E3550 | 355.00 | 7.00 |
| E3650 | 365.00 | 7.00 |
| E3750 | 375.00 | 7.00 |
| E3870 | 387.00 | 7.00 |
| E4000 | 400.00 | 7.00 |
| E4120 | 412.00 | 7.00 |
| E4250 | 425.00 | 7.00 |
| E4370 | 437.00 | 7.00 |
| E4500 | 450.00 | 7.00 |
| E4620 | 462.00 | 7.00 |
| E4750 | 475.00 | 7.00 |
| E4870 | 487.00 | 7.00 |
| E5000 | 500.00 | 7.00 |
| E5150 | 515.00 | 7.00 |
| E5300 | 530.00 | 7.00 |
| E5450 | 545.00 | 7.00 |
| E5600 | 560.00 | 7.00 |
| E5800 | 580.00 | 7.00 |
| E6000 | 600.00 | 7.00 |
| E6150 | 615.00 | 7.00 |
| E6300 | 630.00 | 7.00 |
| E6500 | 650.00 | 7.00 |
| E6700 | 670.00 | 7.00 |
Download the printable PDF ISO 3601 O-Ring Size Chart by clicking the above button. If you need our Excel version, please send an email to [email protected].
O-Ring Size Measurement Specifications
To measure an o-ring, you can just measure its inside diameter (ID) and cross section (CS) (also call width or thickness). The outside diameter (OD) can be known according to the formula: OD = ID + CS*2. The above JIS B 2401 O-Ring Size Chart only shows the size number, ID and CS. These full specifications are for your fast-looking up and comparison.
