You can wear a size 9 in one shop, an 8 in another and a 42 in a third, and all three might be the same shoe. Shoe sizing has no single global standard, which is why buying shoes from another country can be a gamble. The sizes you see depend on the system used, the type of shoe, the brand and even the factory.
This guide explains how the main sizing systems work, how to measure your feet properly, and how to make confident decisions when shopping online.
The main sizing systems
- United States and Canada. Numeric sizes with half sizes. Men's and women's sizes are different scales, so a men's 8 is not the same as a women's 8.
- United Kingdom. Also numeric, but the numbers sit lower than US sizes. UK sizes are used in the UK, Ireland and several other countries.
- Europe (EU). Numbers typically in the 35 to 48 range, based on a unit called the Paris point, which is two thirds of a centimetre. That is why EU sizes step in smaller increments than US sizes.
- Centimetres or Mondopoint. Used by some brands and in some countries, this is based on the length of the foot in millimetres or centimetres. It is the most direct system, since the size is simply the foot length.
Men's versus women's sizes
In the US, a rough rule is that a woman's size is about one and a half sizes larger than the same shoe in men's sizing. A men's 8 is about a women's 9.5. This is why unisex trainers are often listed with two sizes, such as "men's 8 / women's 9.5". If you are buying across the men's and women's sections, check the conversion carefully.
Typical equivalents
The table below shows approximate men's equivalents based on common sports brand charts. Real sizes vary by brand, so treat the table as a starting point, not a promise.
| US (men's) | UK | EU (approx.) | Foot length (cm) |
|---|---|---|---|
| 7 | 6 | 40 | 25 |
| 8 | 7 | 41 | 26 |
| 9 | 8 | 42.5 | 27 |
| 10 | 9 | 44 | 28 |
| 11 | 10 | 45 | 29 |
For women's sizes, add about one and a half to the men's US number to find the matching women's US size. For example, men's 8 equals women's 9.5.
How to measure your foot at home
- Place a sheet of paper on a hard floor, with one edge against a wall.
- Stand on the paper with your heel against the wall. Wear the type of socks you will wear with the shoes.
- Have someone mark the tip of your longest toe, or lean forward and mark it yourself, keeping your weight evenly distributed.
- Measure the distance from the wall edge to the mark, in centimetres.
- Repeat for the other foot. Most people have one foot slightly bigger, so use the larger measurement.
Measure in the afternoon or evening, since feet swell a little over the day. Compare your length with the brand's own size chart, which is almost always more reliable than a general conversion table.
Allow room to move
Your foot length is not the same as your shoe length. You need extra space at the front so your toes are not squeezed, and your foot needs to move slightly as you walk. A common guideline is to leave roughly a thumb's width, or about one centimetre, between the longest toe and the end of the shoe. Running shoes often benefit from a little extra, since feet swell during exercise.
Width matters too
Length is only half the story. If a shoe feels tight across the ball of your foot even though the length is right, you may need a wider fit. Some brands offer widths labelled narrow, regular, wide and extra wide, using letters such as B, D or E. Choosing the right width can make an uncomfortable shoe feel fine.
Why brands vary
Each brand builds its shoes on a "last", a foot-shaped mould, and the last differs between brands and between styles. A slim leather dress shoe and a chunky trainer in the same nominal size can feel quite different. Different factories and countries of manufacture can add small variations too. That is why it helps to check reviews for comments such as "runs small" or "fits true to size".
Tips for buying shoes online
- Use the brand's size chart. Measure your foot in centimetres and compare it with the chart for the exact model.
- Read the reviews. Look for notes on length, width and break-in time.
- Check the returns policy. Free returns or exchanges make it much easier to try sizes.
- Order two sizes when unsure. If the policy allows, keep the one that fits and send the other back.
- Try them on indoors. Walk on a carpet first so you can return them if they are not right.
- Consider the occasion. Sports shoes, boots and sandals often fit differently from everyday shoes.
Shoes for children
Children's feet grow quickly, and shoes that are too small can be uncomfortable. It is worth re-measuring regularly, since a child may go up a size every few months when they are young. Leave a little growing room, but avoid shoes that are much too big, which can cause tripping.
Converting quickly
When you are looking at a size chart in a different system, a converter saves time and reduces mistakes. The Shoe Size International Converter on LoveBloom lets you switch between US, UK and EU sizes in a click, and it is handy for shopping on international websites or planning gifts. If you are shopping for jewellery too, our ring size guide covers the same kind of conversion for rings, and our piece on daily routines has tips for feeling good from head to toe.
In the end, the best fit is the one that feels comfortable when you stand, walk and move. Use numbers as a guide and trust your feet to have the final say.
Size conversions are approximate and vary by brand. Always check the brand's own size chart.