O-ring size identification

O-Ring Size Selector

Have an O-ring measurement but not the dash number? Enter the nominal dimensions and compare the closest AS568 sizes.

Dimensional identification

Find an AS568 O-Ring from Measurements

Enter nominal O-ring inside diameter and cross-section. Results are ranked by dimensional closeness; this does not certify interchangeability.

How the match works

The selector compares your dimensions against the 349 AS568 main-table sizes. ID and cross-section carry the most weight; optional OD provides an additional check.

What it does not determine

A dimensional match does not establish material compatibility, pressure rating, temperature range, hardness, gland suitability or interchangeability with another standard.

Need groove checks?

Once you identify a size, use the Groove Design Check to calculate preliminary squeeze, fill estimate and installation stretch.