Shoe Size Converter
UK, US, EU and centimetre sizes side by side, with the measurement that actually means something.
In short
Shoe sizes convert through foot length in centimetres, which is the only measurement that means the same thing everywhere. A UK size is roughly one less than the men’s US size and about 1.5 less than the women’s US size, but brands vary enough that measuring your foot beats converting a remembered number.
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Measure your foot. It is the only number that transfers
Every conversion here goes through foot length in centimetres, because that is the one measurement that means the same thing in every country and every brand.
- Put a sheet of paper on a hard floor against a wall.
- Stand on it with your heel touching the wall, weight on the foot.
- Mark the paper at the end of your longest toe. Which is not always the big toe.
- Measure from the wall edge to the mark, in centimetres.
- Repeat for the other foot and use the larger measurement.
Do it in the evening. Feet swell through the day and can be nearly a centimetre longer by evening than first thing. A shoe fitted in the morning is often uncomfortable by six o'clock.
Wear the socks you'll actually use. Thick walking socks change the fit by roughly half a size.
Roughly how the systems relate
| System | Based on | Note |
|---|---|---|
| UK | Barleycorns, a third of an inch | Starts from a child's size 0 |
| US men | Same scale as UK | About 1 size larger than UK |
| US women | Same scale, offset again | About 1.5–2 larger than UK |
| EU (Paris point) | Two-thirds of a centimetre | Measures the last, not the foot |
| Japan / Mondopoint | Foot length in centimetres | The only genuinely logical one |
The Japanese system is simply your foot length, which is why it's used for ski boots and military footwear where fit actually matters. Everyone else is working from an eighteenth-century unit based on grains of barley.
Why brands disagree with each other
There is no enforced standard. A manufacturer decides what its size 9 means, builds a last accordingly, and that last differs from every other manufacturer's.
In practice this means a full size of variation between brands is normal, and half a size is unremarkable even between models from the same brand. Running shoes commonly run small; some fashion brands run notably large.
So use the conversion to get in the right region, then check the brand's own chart, most publish foot-length measurements per size, and that is the number to match.
Width, which sizing ignores entirely
Standard width is D for men and B for women. Wider fittings are marked E, EE or 2E, narrower ones C or A.
The common mistake is buying a longer shoe to gain width. It works for about a mile: the extra length means your heel slips, the flex point of the shoe no longer sits under the ball of your foot, and you get blisters in new places. Find a wide fitting instead.
Fitting properly
- A centimetre at the toe: roughly a thumb's width past your longest toe.
- The heel should not lift when you walk.
- The widest part of your foot should sit at the widest part of the shoe.
- Try both shoes on. Most people have feet that differ by a few millimetres.
- Walk around properly: several minutes, not two steps on carpet.
- Don't count on breaking them in. Leather gives a little across the width; nothing gets longer.
For running shoes, go about half a size up from your measured fit. Feet swell considerably over distance, and a shoe that fits perfectly at rest will bruise your toenails at mile ten.
Frequently asked questions
How do I measure my foot?
Stand on a sheet of paper against a wall with your heel touching it, mark the end of your longest toe, and measure heel to mark. Do it in the evening, when feet are at their largest, wearing the socks you intend to wear. Measure both feet and use the larger.
Why is my size different between brands?
Because there is no enforced standard. Manufacturers use their own lasts and their own interpretation of a size, so a 9 in one brand can fit like an 8.5 or a 9.5 in another. Sizes are a starting point, not a specification. Which is why the centimetre column is the useful one.
What is the difference between UK and US sizes?
A men's US size is about one larger than the UK equivalent, and a women's US size about 1.5 to 2 larger. So UK 8 is roughly US 9 men's or US 10 women's. EU sizes run on an entirely different scale, in Paris points of two-thirds of a centimetre.
Should I size up for wide feet?
Only as a last resort. Going up a length to gain width also makes the shoe too long, so your foot slides and the flex point sits in the wrong place. Look for a wide fitting, marked E, EE or 2E. Before you change length.
How much room should there be at the toe?
About a centimetre, or roughly a thumb's width, between your longest toe and the end. Feet lengthen under load, so a shoe that fits perfectly standing still will be too short after a few miles.