Shoe size conversion charts

How do shoe size systems differ?

All three major systems (US, UK, EU) measure the same thing — foot length — but start from different zero points and use different units. US men's uses the barleycorn (⅓ inch = 8.47 mm), starting from a size 0 at one barleycorn above zero. UK sizes use the same unit but from a different origin — UK runs one full size below US men's for the same foot length. EU uses the Paris point (⅔ cm = 6.67 mm) with a different starting offset. Because the unit sizes differ, the gaps are not constant across the full range.

What is US size 9 in EU?

US men's size 9 = EU 42 on the Paris-point formula. A US 9 foot is approximately 269–271 mm long; EU 42 = 28 cm × 1.5 = 42. The conversion is approximate because EU rounds to whole numbers — there is no EU 42.5. See the full table at US to EU conversion.

What is the formula to convert US to UK shoe size?

UK = US men's − 0.5 for the same foot length (US and UK share the barleycorn unit but UK starts one barleycorn lower). So US 9 ≈ UK 8.5, US 10 ≈ UK 9.5. For women's: women's UK ≈ US women's − 2.5 (women's US is 1.5 sizes above men's US for the same foot, and UK is 0.5 below men's US). See the full US to UK chart.

Is EU shoe size the same as CM?

No — they are different conversions of the same foot length. CM (Mondopoint) is foot length in centimetres, so a 270 mm foot = 27.0 CM. EU uses the Paris-point formula: 270 mm = 27 cm × 1.5 = EU 40.5 → rounds to EU 41. The CM number is always smaller than the EU number for the same foot. See US to CM / Mondopoint chart.

Why does EU size rounding matter?

EU always rounds to the nearest whole Paris point (6.67 mm). A foot of 263 mm and a foot of 269 mm can both round to EU 40 — a 6 mm range at a single label. This is why EU-only charts lose accuracy at the edges of each size, and why foot length in millimetres is the definitive reference. Our converter always shows the raw (un-rounded) Paris-point value alongside the rounded EU label.