How to find your ring size: a practical guide to measuring at home

Buying a ring online or commissioning a bespoke piece involves a step that worries many people: knowing the size. The good news is you can measure fairly accurately at home, as long as you avoid a few common mistakes.

Why millimetres are safest

There are several ring-size scales worldwide — Portuguese, European, US, UK — and conversion charts don't always agree. The safest way to communicate a size is in millimetres: the inside circumference of the ring or its inside diameter. With that number any jeweller knows exactly what's needed.

Method 1: from a ring that already fits

The most reliable method, if you have a ring worn on the same finger that fits well.

Place the ring on paper and measure the inside diameter with a ruler, inner edge to inner edge, at the widest point.
Better still, use a caliper on the inside.
Measure in two or three directions: many rings are slightly oval.

Mind the ring type: a thin and a wide ring of the same size don't feel the same. If your reference ring is very different in width from the one you want, tell us.

Method 2: with a strip of paper

Cut a strip of paper about 1 cm wide. Paper, not string — string stretches and misleads.
Wrap it around the base of your finger without squeezing. It should slide over the knuckle with slight resistance.
Mark where the paper overlaps.
Unroll and measure with a ruler in millimetres. That's the circumference.

Measure two or three times; if values differ, use the larger.

Method 3: at the atelier

If you're in Lisbon, the most accurate way is with a set of ring sizers. Visit the atelier by appointment: it takes a minute.

The most common mistakes

Measuring with cold fingers. Fingers shrink in the cold and swell in the heat. Measure at the end of the day at a normal temperature.
Forgetting the knuckle. The ring has to pass over it. If your knuckle is large, it decides the size, not the base.
Using string or thread. It stretches and gives smaller values.
Measuring the wrong finger. Your dominant hand is usually slightly larger, and the same finger can differ between hands.
Ignoring band width. Wide bands fit tighter. For wide bands it's usual to go slightly up.

When the ring is a surprise

"Borrow" for a day a ring the person wears on the same finger and measure it with method 1.
Place that ring on paper and trace the inner circle with a fine pencil.
Ask a friend or relative who knows the size.
If unsure, go slightly bigger: it's easier to make a ring smaller than bigger.

What if the size isn't right?

It's not the end of the world. Most silver and gold rings can be adjusted — we explain how in can a ring be made bigger or smaller?. At the atelier we offer ring resizing in silver and gold, including antique and heirloom rings.

Atelier service

Ring resizing

Make silver and gold rings bigger or smaller. Free quote, a photo is enough.

Request a quote