Measure Ring Size

Finger measurement guide

How to measure a finger for a ring

No ring to copy? Measure the finger itself with a flexible tape or a non-stretch paper strip, then convert the circumference to a size below. Follow the tension and knuckle advice — they are what make a finger measurement trustworthy.

Step-by-step: flexible tape or paper strip

  1. Choose your tool

    A flexible measuring tape is ideal. Otherwise, cut a thin strip of paper — not string, not ribbon, both stretch — about 10 mm wide and long enough to wrap around the finger with overlap.

  2. Wrap at the base of the finger

    Wrap around the exact finger the ring will be worn on, on the same hand, at the base where the ring will sit. Not at the knuckle, and not on a different finger.

  3. Mark the overlap

    With a pen, mark where the tape or strip meets itself. Keep the strip flat against the finger while you mark — lifting it changes the reading.

  4. Lay it flat and read it

    Lay the strip flat against a ruler and read the length in millimetres. That length is the finger circumference. Type it into the calculator below.

  5. Repeat, in the evening, and take the largest

    Measure twice, in the evening with warm hands. If the readings differ, use the largest — a ring must clear the knuckle to be worn at all.

Illustration of measuring around a finger
Illustration only — not a sizing template. Measure your real finger with a tape or paper strip, following the steps above.

Tension and knuckle — the two things that go wrong

Tension: snug, not tight

The strip should be snug against the skin, with no gap, but it should not dent the finger or squeeze it white. Too tight, and you will order a size that hurts; too loose, and the ring will spin or slip off. The right test: the strip should slide over the knuckle with slight resistance when you push it that far.

Knuckle: size for the wider part

If your knuckle is wider than the base of your finger, the ring has to pass over the knuckle first. Measure the knuckle circumference too, and order for the larger of the two — a ring sized only for the base will not go on. If the difference is large, ask a jeweller about sizing beads or a hinged shank instead of guessing.

Warning: Do not measure cold fingers, straight after exercise, or after a very salty meal — fingers shrink when cold and swell with heat and salt. Do not use stretchy string: it gives a longer, looser reading that can be a full size out.

Finger circumference calculator

Decimal numbers are welcome. Use a dot for decimals, for example 16.5.

What you measured

Circumference

Changing the unit reinterprets the number you typed in the new unit — it does not convert it. Re-enter the number if you measured in a different unit.

Note: Tension: snug, not tight — the strip should slide over the knuckle with slight resistance, and should not dent the finger. Knuckle: if your knuckle is wider than the finger base, size for the knuckle, or the ring will not go on. Measure in the evening, with warm hands, and repeat twice, taking the largest reading.

Try an example

Highlight my country's size

Enter a measurement to see your size.

Formulas: circumference = π × diameter; diameter = circumference ÷ π. Matching uses your full, unrounded value; displayed diameter is rounded to 2 decimal places and circumference to 1 decimal place.

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