True Size Ring

Ring sizing guides

Short, practical guides on getting ring size right. Why fingers swell and shrink, the average sizes for men and women, which rings a jeweler can resize, and how US, UK, and EU sizes compare.

A thin gold ring resting on pale linen beside a paper ring sizer strip and a ruler.

Why size changes

Fingers swell and shrink with heat, salt, and the clock. Here is how much, and when to measure.

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Wedding bands in gold, platinum, and dark tungsten arranged on a pale stone surface.

Resizing basics

Tungsten and full eternity bands often cannot be resized. See what can change, and by how much.

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A row of plain gold and silver rings laid out on pale linen beside a millimeter ruler and a steel ring sizing gauge.

Women's sizes

Every US size from 3 to 10 in millimeters, the size jewelers sell most, and when a band width means sizing up.

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A gold ring set inside the printed circles of a paper ring size chart, next to a ruler and a strip of paper marked with a pen.

Find your ring size

Own a ring, a finger, or a printer? Five accurate ways to find your size, plus when to size up.

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Diagram of one ring with a 54.4 mm inside circumference labeled six ways: US 7, UK N 1/2, EU 54, Italy 14, Germany 17.3, and Japan 14.

Sizes by country

US numbers, UK letters, EU millimeters, German diameters, Japan numbers. One chart and the math that links them.

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Three plain men's wedding bands in 4 mm, 6 mm, and 8 mm widths lined up next to a steel millimeter ruler on a grey workbench.

Men's sizes

Every US men's size in millimeters, plus the wide-band rule and how to size a comfort fit band.

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A paper measuring strip wrapped around the base of a finger and marked with a pen, with a silver band and a steel millimeter ruler on the desk below.

Pandora sizes

The Pandora number is the millimeters. See 44 to 64 in US sizes, and when to take the bigger one.

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Cross-section diagram comparing an Oura Gen3 interior, where three sensor bumps cut the 16.76 mm opening down to 15.21 mm of clearance, with the smooth 16.35 mm interior of an Oura Ring 4 at the same size 6.

Oura sizes

Oura numbers look like US sizes but do not measure like them. The Ring 4 chart in mm, and why the Gen3 ran tight.

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A steel millimeter ruler laid across the inside of a plain platinum band on a white desk, with a bank card and a printed page of numbered ring size circles underneath.

Tiffany sizes

Tiffany uses plain US sizes. Every size from 3 to 13 in millimeters, how to use the printed sizer, and what resizes.

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A hand held palm down on pale linen with a plain gold band pulled partway off the ring finger and stopped at the middle knuckle.

How a ring should fit

Snug at the base, a little push at the knuckle, no spinning. Six checks at home, and the fixes when a ring is off.

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Diagram of an inch ruler from 2 to 3 inches marked in sixteenths, with US ring sizes 5.5 to 15.5 lined up above it and 2 1/2 inches falling at a US 10.5.

Sizes in inches

2.5 inches around is a US 10.5. The inch chart, the head math, and why sixteenths are too coarse for ring sizing.

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Diagram of a ring band cut at the bottom of the shank. On the left, a 2.6 mm section is removed to take it down one US size. On the right, a 2.6 mm plug of matching metal is added to take it up one size.

How resizing works

A jeweler cuts the band and takes out or adds about 2.6 mm per size. How it's done, what it costs, and what to check after.

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To-scale diagram of a US size 7 ring opening, 17.32 mm across and 54.41 mm around, beside a US dime 17.91 mm wide that is too big to pass through it, with sizes 6.5 and 7.5 outlined for comparison.

Size 7 rings

17.3 mm across, 54.4 mm around. A 7 in inches and in other countries, who wears one, and a dime test for any ring at home.

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Ready to measure?

Skip the guesswork. The free sizer prints to true scale, with a ruler and a card check on the sheet so the number you read is the number you order.

Open the ring sizer