How to find out a ring size — even in secret

13.08.2026 · Rauno Oidram

The ring mandrel and sizing rings at the Keefirivunts atelier

An Estonian ring size is the finger's circumference in millimetres: size 52 means the finger measures 52 mm around. The most common women's sizes are 52–55, men's 60–66. There are three reliable ways to measure: from an existing ring, with our on-screen sizer right on your phone, or with the thread method. If the result lands between two sizes, choose the larger.

Measuring a ring's inner diameter with callipers at the bench

1. Most accurate: an existing ring

If you can borrow a ring she wears on the same finger (this matters — fingers on the same hand differ by up to two sizes), you have two options:

  • Lay the ring on our on-screen sizer — calibrate with a bank card and read the size in under a minute.
  • Or measure the ring's inner diameter with a ruler and multiply by 3.14. For example 17.2 mm × 3.14 ≈ 54.

2. Without a ring: the thread method

If there is no ring to borrow, wrap a thread or a narrow paper strip around the finger, mark the overlap, and measure the length in millimetres — that number is the size. Measure in the evening — fingers are slimmer in the morning — and never right after sport or in the cold. The most exact answer, though, is ten minutes at the atelier with proper sizing rings on the finger itself.

A thread wrapped around a finger for measuring, close-up of hands

3. Measuring in secret

  • Borrow a ring "for cleaning". A friend or family member asks to try it on or takes it "to be cleaned" — ten minutes at our atelier is enough for an exact measurement.
  • The soap method. Press her ring briefly into a bar of soap or putty and bring us the impression. Less exact, but with our experience usually enough.

Honestly: if the secret measuring fails, it is not a catastrophe. Propose with a size 54 — our first resize is free within the first year and takes a few days.

Between two sizes

Always choose the larger. A tight ring cannot be worn — it sticks at the knuckle. A slightly loose ring can be sized down precisely. Wide bands (over 6 mm) sit tighter: go half a size to a size up for those.

Read next: Ring size · When to order an engagement ring? The timeline that saves the proposal · Buying an engagement ring: five decisions in the right order

Frequently asked

What is the most common women's ring size?

In Estonia the most common women's engagement ring sizes are 52–55, most often 54. Men's wedding bands mostly fall between 60 and 66.

Can a ring be resized later?

Yes. Most rings can be sized up or down by 1–2 sizes; the first resize at Keefirivunts is free within the first year. Full eternity bands are the exception — talk to us first.

How accurate is measuring on a phone screen?

Calibrated against a bank card, the on-screen sizer is accurate to about half a size — enough to tell 52 from 54. If the result sits on a boundary, choose the larger size or spend ten minutes at the atelier for an exact measurement.

What time of day should a finger be measured?

In the evening, at room temperature. Fingers run up to a size slimmer in the morning and in the cold, and temporarily thicker after sport or salty food.

Rauno Oidram examining a stone under the microscope

Rauno Oidram — goldsmith, Keefirivunts

Designs the Keefirivunts rings and chooses the stone that goes into each one.

Still not sure?

An article answers one question. A stone in the hand answers the rest. Come and see — free, with no obligation to order.

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