Navigating between UK and US sneaker sizes can be confusing, especially when shopping internationally or online. This comprehensive guide breaks down everything you need to know about converting between these two major sizing systems, with brand-specific insights to ensure your next pair fits perfectly.
What You'll Learn
Understanding UK vs US Sizing Systems
Before diving into conversion charts, it's important to understand the fundamental differences between these two sizing systems:
Historical origins:
UK sizing is based on the 'barleycorn' measurement system from the 14th century, while US sizing adapted this system with slight modifications
Size increments:
Both systems use 1/3 inch (8.46mm) increments between whole sizes
Starting point:
The scales have different zero points, which creates the consistent difference between them
General rule:
US men's sizes are typically 0.5 size larger than UK (UK 9 = US 9.5), while US women's are 2 sizes larger (UK 5 = US 7)
Men's Conversion:
US Size = UK Size + 0.5
Women's Conversion:
US Size = UK Size + 2
Men's UK to US Size Conversion Chart
For men's sneakers, US sizes are typically 0.5 size larger than UK sizes. Use this comprehensive chart for quick reference:
| UK Size | US Size | EU Size | Foot Length (cm) |
|---|---|---|---|
| UK 5 | US 5.5 | EU 39 | 24.0 cm |
| UK 6 | US 6.5 | EU 40 | 25.0 cm |
| UK 7 | US 7.5 | EU 41 | 26.0 cm |
| UK 8 | US 8.5 | EU 42 | 27.0 cm |
| UK 9 | US 9.5 | EU 43 | 28.0 cm |
| UK 10 | US 10.5 | EU 44 | 29.0 cm |
| UK 11 | US 11.5 | EU 45 | 30.0 cm |
| UK 12 | US 12.5 | EU 46 | 31.0 cm |
US Men's Size = UK Size + 0.5
Example: If you wear a UK 8, you'll typically wear a US 8.5 in men's sneakers.
Women's UK to US Size Conversion Chart
For women's sneakers, the difference is typically 2 full sizes, with US sizes being larger than UK sizes:
| UK Size | US Size | EU Size | Foot Length (cm) |
|---|---|---|---|
| UK 2 | US 4 | EU 35 | 21.6 cm |
| UK 2.5 | US 4.5 | EU 35-36 | 22.0 cm |
| UK 3 | US 5 | EU 36 | 22.4 cm |
| UK 3.5 | US 5.5 | EU 36-37 | 22.9 cm |
| UK 4 | US 6 | EU 37 | 23.3 cm |
| UK 4.5 | US 6.5 | EU 37-38 | 23.7 cm |
| UK 5 | US 7 | EU 38 | 24.1 cm |
| UK 5.5 | US 7.5 | EU 38-39 | 24.5 cm |
| UK 6 | US 8 | EU 39 | 25.0 cm |
| UK 6.5 | US 8.5 | EU 39-40 | 25.4 cm |
| UK 7 | US 9 | EU 40 | 25.8 cm |
| UK 7.5 | US 9.5 | EU 41 | 26.2 cm |
| UK 8 | US 10 | EU 41-42 | 26.7 cm |
| UK 8.5 | US 10.5 | EU 42 | 27.1 cm |
US Women's Size = UK Size + 2
Example: If you wear a UK 5, you'll typically wear a US 7 in women's sneakers.
Children's UK to US Size Conversion
Children's sizing can be particularly confusing as it follows different patterns in different regions:
| UK Size | US Size | EU Size | Foot Length (cm) |
|---|---|---|---|
| UK 10C | US 10.5C | EU 28 | 17.1 cm |
| UK 10.5C | US 11C | EU 29 | 17.5 cm |
| UK 11C | US 11.5C | EU 30 | 18.0 cm |
| UK 11.5C | US 12C | EU 30.5 | 18.4 cm |
| UK 12C | US 12.5C | EU 31 | 18.8 cm |
| UK 12.5C | US 13C | EU 31.5 | 19.2 cm |
| UK 13C | US 13.5C | EU 32 | 19.7 cm |
| UK 13.5C | US 1Y | EU 33 | 20.1 cm |
| UK 1 | US 1.5Y | EU 33.5 | 20.5 cm |
| UK 1.5 | US 2Y | EU 34 | 20.9 cm |
| UK 2 | US 2.5Y | EU 34.5 | 21.3 cm |
| UK 2.5 | US 3Y | EU 35 | 21.8 cm |
| UK 3 | US 3.5Y | EU 35.5 | 22.2 cm |
| UK 3.5 | US 4Y | EU 36 | 22.6 cm |
| UK 4 | US 4.5Y | EU 36.5 | 23.0 cm |
| UK 4.5 | US 5Y | EU 37 | 23.5 cm |
| UK 5 | US 5.5Y | EU 37.5 | 23.9 cm |
Note: In children's sizing, 'C' typically denotes Child sizes, while 'Y' denotes Youth sizes in the US system.
Brand-Specific Sizing Differences
While the general conversion rules apply across most brands, there are notable exceptions and quirks to be aware of:
Nike & Jordan
- Generally follows standard UK to US conversion
- Some performance basketball models run narrow
- Air Force 1s typically run large (consider sizing down 0.5)
- Dunk SBs often run small due to padded tongue
- Jordan 1s are generally true to size but slightly narrow
Adidas & Yeezy
- Standard conversion applies to most models
- Yeezy 350 V2s typically run small (size up 0.5)
- Yeezy 700s are generally true to size
- Ultra Boosts often run small (consider sizing up 0.5)
- Adidas Superstars and Stan Smiths run large
New Balance
- Offers multiple width options (important consideration)
- Made in UK models can run 0.5 size larger
- 990 series generally runs true to size
- 550s and 2002Rs often run large
- Numeric skate shoes run small (size up 0.5-1)
Converse
- Runs large compared to standard sizing
- Typically size down 0.5-1 full size from your usual UK size
- Chuck 70s fit more true to size than regular All Stars
- High tops and low tops fit similarly
- One Stars run closer to true size
Common Sizing Mistakes to Avoid
❌ Assuming all brands follow the same conversion
✅ Always check brand-specific sizing guides when available
❌ Ignoring width measurements
✅ Length alone doesn't determine fit, especially for brands like New Balance that offer width options
❌ Forgetting about half sizes
✅ Half sizes can make a significant difference in comfort, especially for wider feet
❌ Not accounting for material differences
✅ Leather sneakers will stretch and conform over time, while knit materials have more immediate give
❌ Overlooking insole measurements
✅ When buying pre-owned sneakers, ask for insole measurements in centimeters for the most accurate comparison
How to Measure Your Feet for Accurate Sizing
For the most accurate sizing, we recommend measuring your feet and comparing to the foot length in centimeters:
Gather materials
You'll need a piece of paper, pencil, ruler, and the socks you typically wear with sneakers
Evening measurement
Measure in the evening when your feet are at their largest due to natural swelling throughout the day
Stand on paper
Place the paper on a hard floor against a wall. Stand on it with your heel touching the wall
Mark longest toe
Have someone mark the position of your longest toe on the paper
Measure length
Measure the distance from the wall (heel) to the mark (toe) in centimeters
Compare to charts
Use the foot length column in our charts above to find your size
Consider width
For a complete measurement, also measure the widest part of your foot
Special Considerations for Online Shopping
Tips for Buying Sneakers Online
Conclusion: Finding Your Perfect Fit
Converting between UK and US sneaker sizes doesn't have to be complicated. While the general rule of thumb is that US men's sizes are 0.5 size larger than UK (UK+0.5) and US women's sizes are 2 sizes larger (UK+2), brand-specific variations and your unique foot shape are important factors to consider.
At Offseason Shoes, we provide detailed sizing information with all our past-season sneakers, including insole measurements and fit notes to help you make the most informed decision. Remember that the perfect fit should feel comfortable from heel to toe, with about a thumb's width (1-1.5cm) of space between your longest toe and the end of the shoe.
For brand-specific sizing guides, check out our detailed articles on Jordan, Yeezy, and New Balance sizing.