How to measure your ring size

This is the method we trust most, because it measures a ring rather than a finger. Take a ring that fits the intended finger comfortably, and measure the inside diameter, edge to edge across the widest point, with a ruler that has millimeters.

Read the number to the nearest half millimeter. A 16.9 mm inner diameter is a US 6.5, or a European 53. Put that number into the converter above and you have all three systems at once.

Cut a strip of paper about 4 mm wide, wrap it snugly around the base of the finger, mark where it overlaps and lay it flat against a ruler. The length in millimeters is your European size directly, because the European system is the circumference.

Paper is better than string, which stretches. Wrap it firmly enough that it cannot slide off but loosely enough that it does not dent the skin. Then check it can pass over the knuckle before you trust it.

Print the sizer below at exactly 100 percent, with page scaling switched off, and verify the calibration ruler on the sheet with a real ruler before you cut anything. A single percent of print scaling is roughly half a size.

Cut out the strip, slide it around your finger and read the size at the arrow. Do it twice, at two different times of day.

Any jeweler will size your finger with a set of steel rings in a minute, usually for free. Steel sizers are the standard the whole trade works from, so if you are buying an expensive antique ring, this is worth the walk.

Ask for the size in millimeters as well as the US number. Millimeters travel between systems without rounding.

Temperature comes first. Fingers can change close to a full size between a cold morning and a warm evening, and they swell after exercise, salt, alcohol and long flights. Measure at the end of a normal day, at normal room temperature, and measure at least twice.

Band width comes second. A wide band takes up more of the finger and feels tighter, so a 6 mm Art Deco band usually needs a quarter to a half size more than a 2 mm one. Old rings are often wider than they look in a photograph.

Knuckles come third. If your knuckle is noticeably larger than the base of your finger, size so the ring passes the knuckle with a little effort, then accept that it will be slightly loose at the base. A ring that fits the base but not the knuckle simply cannot be worn.

On every ring in our collection we publish the size in both systems, so you never have to convert anything yourself. The European number is the inner circumference in millimeters, exactly as it is measured in our workshop in the Netherlands.

Because the two systems do not line up perfectly, some European sizes fall between US half sizes. Where that happens we show the nearest US size and mark it as approximate, which is how a jeweler would describe it too.

Often, but not always, and it is a decision worth making before you buy. A plain gold shank can usually move one to two sizes in either direction safely. An eternity band set all the way around, a shank with original hand engraving, or a ring with a hallmark on the band frequently cannot be cut without destroying part of what makes it valuable.

Where resizing is not advisable we say so on the product page. Sizing beads, a spring insert or a discreet inner sleeve keep the ring original and still make it wearable. Ask us on a video call and we will tell you honestly what a specific ring can take.