Circumference (mm) to Diameter (mm) Ring Size (Comfort Fit)

1 Circumference value = 0.31831 Diameter value · profile-dependent conversion · context: size system and fit profile

Direct Answer

1 Circumference value equals 0.31831 Diameter value

This result depends on the selected profile context: size system and fit profile.

For 4 Circumference value, this profile returns 1.27324 Diameter value.

Converter Calculator

1 Circumference (mm) value =
0.31831 Diameter (mm) value

Explanation

Circumference (mm) converts to Diameter (mm) by normalizing to ring diameter in millimeters, then remapping to the target system. Fit profile fixed: Comfort Fit.

Circumference value to Diameter value is profile-bound here: the selected size system and fit profile controls the mapping used by calculator and reference table.

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Keep the same profile in both directions to avoid mixing lookup systems that use different size mappings.

Method & Reference (Verified)

  • Method basis: profile-bound mapping; constants depend on the selected profile encoded in the route.
  • Profile reference: size system and fit profile.
  • Consistency rule: keep the same profile in mirror direction to avoid mixing incompatible mappings.

Common Conversion Values

Circumference (mm) valueDiameter (mm) value
4 1.27324
5 1.591549
6 1.909859
7 2.228169
8 2.546479
9 2.864789
10 3.183099
11 3.501409
12 3.819719
13 4.138029