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Pure Origin, Brilliant Design
PureArcDesign

Ring Size Guide

Client care

Ring Size Guide

PureArcDesign rings are crafted in standard U.S. sizes. Use this guide to compare measurements, measure at home, and understand how a ring should feel on the finger.

Ring size conversion chart

Use the inside circumference measurement to match your U.S. ring size. If you are buying a wider band, stacked ring, or eternity-style setting, contact us before confirming the final size.

U.S. Size Inside Circumference Approx. UK/AU Size
3 44.2 mm F
3.5 45.5 mm G
4 46.8 mm H
4.5 48.0 mm I
5 49.3 mm J 1/2
5.5 50.6 mm K 1/2
6 51.9 mm L 1/2
6.5 53.1 mm M 1/2
7 54.4 mm N 1/2
7.5 55.7 mm O 1/2
8 57.0 mm P 1/2
8.5 58.3 mm Q 1/2
9 59.5 mm R 1/2
9.5 60.8 mm S 1/2
10 62.1 mm T 1/2
10.5 63.4 mm U 1/2
11 64.6 mm V 1/2
11.5 65.9 mm W 1/2
12 67.2 mm X 1/2
12.5 68.5 mm Z
13 69.7 mm Z+1

How to measure ring size at home

A finger being measured at its base with a ring sizing strip

1. Measure finger circumference

Wrap a thin strip of paper, floss, or string around the base of the intended finger. Mark the overlap, lay the strip flat, and read the length against a millimeter ruler.

Finger circumference example millimeters 40455055606570 54.4 mm = US size 7
A plain ring positioned over a millimeter ruler to demonstrate inside diameter measurement

2. Measure an existing ring

Choose a ring that fits the intended finger. Measure straight across the widest part of the opening, from one inside edge to the opposite inside edge. Do not include the metal band.

Inside diameter example millimeters 17.3 mm inside edge to inside edge 0510152025 approx. US size 7
Method 3

Use a printable ring sizer

Print a ring sizer at 100% scale on standard paper. Check the printer scale with a real ruler before cutting, then wrap it snugly around the base of the finger and read the size at the slot.

Measure more than once

Finger size can change with temperature, time of day, hydration, and activity. Measure at room temperature and compare results across different times before finalizing.

How should a ring fit?

A well-fitting ring should slide over the knuckle with slight resistance and sit comfortably without spinning too much or feeling tight. You should be able to remove it without force, but it should not feel loose enough to fall off.

Too tight

The ring leaves a deep mark, feels uncomfortable, or is difficult to remove after normal wear.

Too loose

The ring spins constantly, slides over the knuckle too easily, or feels insecure when your hands are cold.

If you are between sizes

When you are between sizes, sizing up is usually safer than sizing down, especially for engagement rings, wider bands, or fingers with larger knuckles. Quarter sizes may be available for custom pieces.

Unsure about the final size?

Email [email protected] with your measurement, ring style, and whether it is for daily wear. We can help review the fit before production.