Ring size 13 in mm, cm, UK and EU

Ring size 13 in the US means a ring 22.2 mm wide inside and 69.7 mm round. The UK calls the same ring Z½, Europe 70, Japan 27 and India 30.

Ring size 13 in every system

Ring size 13 in mm, cm, UK and EU: every system
US and Canada	13
UK, Ireland, Australia	Z½
Europe (EU)	70
Japan and China	27
India	30
Italy, Spain, Switzerland	30
Across the inside	22.2 mm · 2.22 cm · 0.874 in
Around the inside	69.7 mm · 7.0 cm · 2.74 in

One whole size bigger, US 14, is just under 1 mm wider. All of these numbers are from the standard ring size conversion table.

Check a ring against ring size 13 on your screen

1Match a bank card

The card works like a ruler: nothing on it is read or saved, and a driving licence works too. Only its height counts, so the drawing may run off the edge of a phone. Hold the card flat on the screen, long side across, with its top edge on the drawing's top line. Then move the slider until the drawing's bottom line meets the card's bottom edge.

Optional. Only needed to lay a ring or strip on the screen; typed measurements work without it. Nothing on the card is read or saved.

2Measure

A ring I own My finger Print a sizer

Inside diameter of your ring mm

Lay the ring on the circle, or type the inside diameter if you measured it.

Length of your paper strip mm

Wrap a thin strip of paper around the base of your finger, mark where it overlaps, then measure to the mark.

The circle shows a 17.3 mm ring, drawn for a typical screen.

This size, drawn on your screen

US13

UK Z½ · EU 70 · Japan 27 · India 30

22.2 mm (0.87 in) across the inside · 69.7 mm (2.74 in) around

For a wide band (over 4 mm), go up about half a size, to US 13½.

See every size in the ring size chart · Convert a size you already know

Nearby sizes

Too tight or too loose? Try the size one row up or one row down.

Nearby sizes
US and Canada	UK and Australia	Europe (EU)	Inside diameter (mm)	Circumference (mm)
12	X½	67	21.4	67.2
12¼	Y	68	21.6	67.8
12½	Y½	68	21.8	68.5
12¾	Z	69	22.0	69.1
13	Z½	70	22.2	69.7
13¼	Z1	70	22.4	70.4
13½	Z1 to Z2	71	22.6	71.0
13¾	Z2	72	22.8	71.7
14	Z3	72	23.0	72.3

Common questions about ring size 13

How many millimetres is US ring size 13?

It is 22.2 mm wide inside and 69.7 mm round the inside. In inches, the width is 0.87.

How many centimetres is US ring size 13?

Round the inside it is 7.0 cm, and it is 2.22 cm wide.