O-ring standards

AS568 vs JIS B 2401 O-Ring Sizes

AS568 and JIS B 2401 use different designation systems. Similar nominal dimensions can help with identification, but they are not automatically interchangeable.

Example: AS568-214 vs JIS P-25

Standard	Size	ID (mm)	CS (mm)	OD (mm)
AS568	AS568-214	24.99	3.53	32.05
JIS B 2401	P-25	24.7	3.5	31.7

This is a dimensional comparison. It does not establish formal equivalence or interchangeability.

AS568

AS568 uses dash numbers tied to nominal inside diameter and cross-section. Our site currently contains 349 main-table AS568 entries.

JIS B 2401

JIS B 2401 uses series such as P, G and V. Our current verified P-series dataset is intentionally scoped and should not be treated as the complete standard.

When comparing

Check ID, CS, tolerances, material, application and gland dimensions. A close dimensional match is only the first screening step.

Use the cross-reference tool

Compare O-ring standards