GuidesSize without asking
How to find out someone's ring size without asking
If the ring is a gift, asking for the size spoils the surprise. These are the ways to find it out without them knowing, from the most reliable to the least, and what to do if none works.
Updated on September 27, 2026
The short answer: borrow a ring they wear on that same finger for a while and measure it on the inside; with that measurement, the calculator below gives you the size. If there is no way, order the ring with the size «To be confirmed», or give the gauge first: 17 rings from size 5 to 13, and they pick their own.
1. With a ring they already wear
- Same finger, same hand. The fingers of one hand and the other do not always match, and the ring finger does not measure the same as the middle one.
- Measure it on the inside, edge to edge through the center. With a caliper it comes out almost exact; with a ruler you can be off by half a millimeter, and every millimeter of diameter is 1.23 sizes.
- If you cannot take it with you, lay it on paper and trace the inner edge with a very sharp pencil, then measure the circle calmly. Or take a straight photo from above next to a bank card, which is 85.6 mm long: in the photo, the card works as your ruler.
2. Other clues, less reliable
- An imprint. Press their ring into a bar of soap or a piece of modeling clay and measure the hole it leaves on the inside. It works, but the edge deforms when you pull it out.
- Someone close. A friend or a relative may know it, or ask without raising suspicion.
- Your own finger. If their ring goes up to a certain point on one of your fingers, mark that point and measure around it with a strip of paper. It is the least reliable, because no two fingers are alike.
How close each way gets
| Way | What you need | How close it gets |
|---|---|---|
| One of their rings and a caliper | What you need: A caliper | How close it gets: Almost exact |
| One of their rings and a ruler | What you need: A ruler | How close it gets: Half a size |
| The ring's circle on paper | What you need: A sharp pencil and a ruler | How close it gets: Half a size |
| A photo of the ring next to a card | What you need: Your phone and a bank card | How close it gets: Half a size, if the photo is straight |
| The imprint in soap or clay | What you need: A bar of soap or modeling clay | How close it gets: Up to one size |
| How far their ring goes on your finger | What you need: A strip of paper | How close it gets: One size or more |
If you are between two sizes
Pick the larger one. The Hinge Ring is 5.5 mm wide, and a wide band feels tighter than a thin one of the same size. Also, once cast it cannot be made larger or smaller: the ring size guide explains why. And if it does not fit, you get one free size exchange within 30 days of delivery: you send the ring back and we make another in their size.
If none works
- Order the ring with the size «To be confirmed» in the configurator: before casting we confirm the size with the printed gauge, which we send for free in Bogotá.
- Or give the Ring Size Gauge first, with a note: they pick their size at home and the ring comes later. For Christmas, check the order-by dates.
Turn the measurement into a size
Type the inside diameter of their ring, or the circumference if you measured with a strip of paper.
Calculator
Type the measurement in millimeters.
The Hinge Ring is made in the size you tell us, from 5 to 13, with an inside engraving if you want. More ideas in the gift guide.
More ideas