How to Measure Ring Size
A complete guide to finding the perfect fit for your special ring.
Choosing the perfect ring size is essential for comfort and fit. Whether you’re buying an engagement ring, a wedding band, or just a special piece of jewelry, here’s a step-by-step guide on how to measure your ring size at home.
Step 1: Use a Piece of String or Paper Strip
Take a thin piece of string or a strip of paper (about 1 cm wide).
Wrap it around the base of the finger you want to measure. Ensure it is snug, but not too tight.
Mark the point where the string or paper overlaps.
Measure the length from the starting point to the mark using a ruler. This is your finger’s circumference.
Step 2: Compare to a Ring Size Chart
Convert your finger circumference to a ring size using the chart below. If you’re in between sizes, opt for the larger size for comfort.
International Ring Size Conversion Chart
| Circumference (mm) | Diameter (mm) | US/Canada | UK/Australia | EU | Japan |
|---|---|---|---|---|---|
| 44.2 | 14.1 | 3 | F | 44 | 4 |
| 46.8 | 14.9 | 4 | H | 47 | 7 |
| 49.3 | 15.7 | 5 | J | 49 | 9 |
| 51.9 | 16.5 | 6 | L | 52 | 12 |
| 54.4 | 17.3 | 7 | N | 54 | 14 |
| 57.0 | 18.1 | 8 | P | 57 | 16 |
| 59.5 | 18.9 | 9 | R | 59 | 18 |
| 62.1 | 19.8 | 10 | T | 62 | 20 |
| 64.6 | 20.6 | 11 | V | 64 | 23 |
| 67.2 | 21.4 | 12 | X | 67 | 25 |
| 69.7 | 22.2 | 13 | Z | 69 | 27 |
Tips for Accurate Ring Sizing
Avoid measuring cold fingers – they tend to shrink. Measure when your hands are warm.
Measure your knuckle – if larger than the base, choose a size in between for comfort.
Consider width – wider bands feel tighter, so size up slightly for wider designs.
Regional Sizing Differences
US/Canada: Numeric system increasing by ~0.4 mm per size.
UK/Australia: Alphabetical scale (A to Z).
Europe: Millimeter-based circumference.
Japan: Numeric system similar to Europe but unique increments.
How to Measure Her Ring Size for a Surprise
Planning a surprise proposal or ring gift? Here are clever ways to find her size discreetly:
Borrow a ring she wears on the correct finger and get it measured by a jeweler.
Trace the inside of one of her rings on paper and bring it to a store for sizing.
Ask her close friends or family—they may already know or can find out.
Visit a jewelry store together under a casual pretense and observe her size.
Measure her finger while she sleeps using string or soft tape—only if safe!
Use a mobile ring sizer app to match the diameter of her existing ring.
Propose with a temporary ring and resize later—it keeps the surprise intact.