US to UK Men's Jacket Sizes Converter
Find your UK size from a US size. Pick your size below, then read the full chart and fit notes.
US to UK Men's Jacket Sizes chart
Jackets & suits
| US | UK | Chest (cm) |
|---|---|---|
| 34 | 34 | 86 |
| 36 | 36 | 91 |
| 38 | 38 | 97 |
| 40 | 40 | 102 |
| 42 | 42 | 107 |
| 44 | 44 | 112 |
| 46 | 46 | 117 |
| 48 | 48 | 122 |
| 50 | 50 | 127 |
How the conversion works
Men's jackets, blazers and suits in the US and UK are both sized by chest circumference in inches, so the numbers are the same on either side of the Atlantic. The confusion usually comes from letter sizes (S, M, L) and from European labels, which use a different scale.
For jackets, a US size equals the UK size: a 40 in the US is a 40 in the UK. Add 10 to get the EU size.
Getting the right fit
The number on a suit jacket is the chest measurement it is designed to fit, not the garment's actual dimensions. Measure around the fullest part of your chest, under your arms and over your shoulder blades, keeping the tape level, and round to the nearest even number. Add an "S", "R" or "L" for short, regular or long if the brand offers them.
Frequently asked questions
Is a US size 40 jacket the same as a UK 40?
Yes. Both countries use chest size in inches, so a 40 in the US is a 40 in the UK, which corresponds to roughly 102 cm. The EU equivalent is 50.
Are these size conversions exact?
No. Clothing and shoe sizes are conventions rather than measurements, and every brand cuts its garments a little differently. Treat the result as a reliable starting point, then confirm with the retailer's own size chart and customer reviews.
What should I do if I am between two sizes?
Compare your body measurements against the brand's chart. If you are still undecided, choose the larger size for a relaxed fit or if the item does not stretch, and the smaller size if the garment is stretchy and you prefer a snug fit.