Free Men's Clothing Size Converter
Convert men's clothing sizes across US/CA, UK, EU, IT, FR, AU, and JP systems. Full size table with chest measurements. Free, no sign-up.
Exact Conversion Formula & Multipliers
Men’s clothing sizes are conventions built on body measurements rather than fixed multipliers. US and UK suit and jacket sizes are the chest girth in inches (a 40 jacket fits a 40-inch chest); European, Italian and French jacket sizes are roughly half the chest girth in centimetres, which works out to the US/UK size + 10 (US 40 = EU 50). Letter sizes are not standardised; this chart uses the common mapping S ≈ 34–36, M ≈ 38–40, L ≈ 42–44. Japanese letter sizes are assigned by chest-girth bands (S ≈ 80–88 cm, M ≈ 88–96, L ≈ 96–104, LL ≈ 104–112 under JIS L 4004), so a US M is usually a Japanese L. Shirt collar sizes are neck girth: 15 in ≈ 38 cm.
Practical Real-World Scenarios
- Online international shopping: buying from a European retailer requires converting US or UK size labels to EU numbering, where the offset isn't always the same simple formula across brands.
- Travel and business attire: purchasing a replacement shirt or suit while traveling abroad means navigating unfamiliar local size charts rather than relying on a home-country size number.
- Gift-giving across borders: buying clothing as a gift for someone in another country requires converting their usual size to the local sizing system of the store.
Historical & Technical Background
Clothing sizing systems emerged independently in different countries as the ready-to-wear garment industry industrialized in the 19th and 20th centuries, each built around that country's typical body-measurement conventions rather than any shared international standard. Efforts like ISO 3635 and 3636 attempted to harmonize sizing internationally, but adoption remains inconsistent — which is why size charts, rather than a single universal formula, remain the most reliable conversion method for clothing to this day.
Precision & Accuracy Statement
Clothing sizes are national conventions, not physical constants. This chart follows the body-measurement rules summarised in the Wikipedia “Clothing sizes” article and is meant as a starting point: women’s US size ≈ bust (in) − 28, UK = US + 4, DE = US + 30, FR/ES = US + 32, IT = US + 36, JP = the JIS L 4005 size with the nearest bust girth; men’s US/UK suit size = chest (in), EU/IT/FR = US/UK + 10 (≈ chest cm ÷ 2). Letter sizes (S, M, L…) are not standardised and vary by brand. Only 1 inch = 2.54 cm is an exact constant; measure yourself and check the brand’s chart.
How This Converter Works
Men’s clothing is labelled with letters (XS–4XL) in some regions and numbers in others. US/UK jacket sizes equal the chest in inches, and EU/IT/FR sizes are about half the chest in cm, i.e. the US/UK size + 10. Measure your chest and use the table to find your size in any region.
Common Conversions
| Int'l | US / UK suit | EU / IT / FR | JP (letter, approx.) | Chest (in) | Chest (cm) |
|---|---|---|---|---|---|
| S | 34 | 44 | S | 34 | 86 |
| S | 36 | 46 | M | 36 | 91 |
| M | 38 | 48 | L | 38 | 97 |
| M | 40 | 50 | L | 40 | 102 |
| L | 42 | 52 | LL | 42 | 107 |
| L | 44 | 54 | LL | 44 | 112 |
| XL | 46 | 56 | 3L | 46 | 117 |
| XXL | 48 | 58 | 4L | 48 | 122 |