How to Find Your Ring Size
The reliable ways to measure, the ones to avoid, and what to do when the ring is a surprise.
Reviewed by Adnan Ali, Graduate, GIA Diamond Grading · Updated 2026-09-17
UK ring sizes are lettered, from A upwards, with half sizes in between. Getting the size right matters more with a made-to-order ring, because it is built for the finger size you give us rather than taken from a tray.
The most reliable way
Have the finger measured by a jeweller with a proper set of sizing rings. Measure at the end of the day, when fingers are at their largest, and not when your hands are cold. If a knuckle is noticeably larger than the base of the finger, the ring has to pass over the knuckle, so size for that.
Using a ring that already fits
If the person already wears a ring on the same finger, measure the inside diameter of that ring in millimetres, straight across the middle, or ask us and we will help you convert it. Make sure it is from the same finger and the same hand: sizes differ between fingers and between hands.
Methods to avoid
- Paper strips and string — they stretch and twist, and usually read a size too large.
- Printable sizers — a small printer scaling error changes the result.
- Guessing from clothing or glove sizes.
When the ring is a surprise
Borrow a ring they wear on the right finger — ideally the ring finger of the hand they will wear it on — just long enough to measure its inside diameter, and send us the measurement. If that is impossible, a close friend or family member may know their size. When in real doubt, going slightly larger is the safer error: a ring that is a little loose can still be worn home, and a plain band can be resized.
Wide bands and eternity rings
A wide band covers more of the finger and tends to feel tighter than a narrow one of the same size, so many people go up a half size for a wide band. Take extra care with full-eternity rings and designs with stones set into the shank: they cannot be resized afterwards, because there is no plain metal to work with.
If the size turns out wrong
Resizing after purchase is free: you cover the postage to send the ring to us and we cover the return postage. It is not possible on full-eternity rings or on designs with stones set into the shank — those have to be remade, and we would quote for that first.