Jewelry tools
Ring Size Converter
Convert EU / US / UK / JP ring sizes. Calculate from string measurement, diameter, or pick from a grid.
How to use the converter?
Choose a method: measuring with string → enter circumference in mm (= EU size). Have a ring → enter inner diameter. Know your size → select system and tap a tile. The calculator shows equivalents in all systems.
Finger circumference54mm
44mm70mm
mm - Wrap a string or paper strip around your finger, mark the overlap, measure in mm.
Your size
54
exact
Ø mm17.2 mm
Circumf. mm54.0 mm
US7
UKM
JP14
How to measure your ring size
Nothing to measure with?Print our sizer. A printed strip beats string, because it does not stretch and you never transfer the result to a ruler.Printable ring sizer- Measure in the afternoon - fingers are largest then.
- String method: wrap snugly around the base of your finger, mark where it meets, cut and measure in mm = EU size.
- Paper strip (1 cm wide) instead of string - easier to measure straight.
- Existing ring: measure inner diameter with calipers. No calipers? Trace on paper, measure the circle.
- Knuckle wider than base? Measure both; choose the larger size.
Sizes are approximate. Always verify with a physical ring sizer.
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