Measure a ring you already own
- Pick a ring that fits the finger you're sizing.
- Measure the inside diameter in millimetres.
- Match the measurement to the chart below.
Tip: a millimetre ruler reads inside-edge to inside-edge across the ring.
Ring Size Guide
Finding your size is the difference between a ring you wear forever and a ring that lives in a drawer. Use either method below — both take under five minutes — or download our printable sizer.
Use our printable sizer
- Download and print at 100% scale on letter paper.
- Verify the calibration bar measures exactly 2 in (50 mm).
- Cut, wrap around your finger, read the size through the slot.
Convert between regions
Type or pick a size in any region — we'll convert to the rest, including inside circumference in millimetres.
Full conversion chart
| US / Canada | UK / AU / IE | France | Germany / RU | India / CN / JP | Italy / Spain | mm (circ.) | in (circ.) |
|---|
Sizing tips
What if I'm between two sizes?
Round up. A ring that's slightly loose can be resized down; a ring that's too tight is harder to enlarge without affecting the setting.
When is the best time of day to measure?
Late afternoon or early evening. Fingers swell in heat and shrink in cold — measuring first thing in the morning or right after exercise will give you a misleading result.
Do wide bands fit differently?
Yes. Bands wider than 6 mm sit tighter than thin bands at the same nominal size. If you're choosing a wide band, go up a quarter to a half size.
Should I size for my knuckle or the base of my finger?
Whichever is larger — the ring needs to pass over the knuckle but should rest comfortably at the base. If your knuckle is much larger, talk to us about sizing beads.
Can my ring be resized later?
Most solitaires and standard bands can be resized within a few sizes. Eternity bands, tension settings, and patterned bands often cannot. When in doubt, ask before you buy.
Still unsure?
Email care@diyona.com and we'll send a complimentary ring sizer to your door.
