Ring Size Calculator
Don't guess your ring size. Use our free calculator to find your exact fit in US, UK, EU and Japanese sizes.
1
How will you measure?
String or Paper
I have string, paper, or a flexible tape
Existing Ring
I have a ring that already fits well
I Know My Size
Convert between size systems
How to measure with string:
- Cut a thin strip of paper (or use string, dental floss, or a thin ribbon)
- Wrap it snugly around the base of the finger you want to wear the ring on — not too tight, not too loose
- Mark where the strip overlaps with a pen
- Lay it flat on a ruler and measure the length in millimeters
- Enter that number below
No ruler at hand?
Open the ruler on your phone's screen (search "ruler app" in your app store), or hold the paper strip against a credit card — a standard card is exactly 85.6mm long, so you can estimate from that.
How to measure with an existing ring:
- Choose a ring that fits the correct finger comfortably
- Place it flat on a ruler or flat surface
- Measure the inside distance from one inner edge straight across to the other (the diameter)
- Read the measurement in millimeters and enter below
No ruler at hand?
Place the ring on a piece of paper, trace the inside circle with a pencil, then measure that circle's width with any straight edge. A US dime is 17.9mm — almost exactly a size 7.5.
Convert your existing size
- Select which sizing system you already know (US, UK, EU, or Japan)
- Enter your size number or letter
- We'll convert it to all other systems instantly
Where to find your size?
Check the inside of a ring you own — many have the size engraved. Or check past order confirmations from other jewelry brands.
2
Enter your measurement
Circumference (the length you measured)
millimeters (mm) — typically between 44 and 70
Inner diameter of the ring
millimeters (mm) — typically between 14 and 22
Your known size
Most delicate rings are 2–4mm. If yours is a chunky statement band (6mm or wider), it covers more skin and feels tighter — check this box and we'll bump up half a size.
Your ring size
—US
Measured · Ready to shop
A US — maps to — mm circumference — your bedrock number for any ring.
International sizes
Fit note
Fingers swell in evening — measure then for accuracy.
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Full conversion & detail
Your Ring Size
US / Canada
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UK / Australia
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EU / Europe
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Japan
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Not sure? Measure twice at different times of day. Fingers are largest in the evening and after exercise.
Quick Sizing Tips
Measure in the evening. Fingers shrink when cold and swell when warm. Evening at room temperature gives the most reliable reading.
Between sizes? Go up. A slightly loose ring beats a tight one. Most rings can be sized down more easily than up.
Each finger is different. Your dominant hand is usually slightly larger. Always measure the exact finger you'll wear the ring on.
Knuckle matters. If your knuckle is significantly larger than the base of your finger, measure both and go with the average.
International Ring Size Chart
| US | UK | EU | JP | Dia. | Circ. |
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Each handcrafted to order in any US size 3–13 · S925 · Free shipping worldwide
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