Your chest measurement is the key to several different labels: the letter on a T-shirt, the number on a jacket, and the European suit size on a continental label. This calculator takes one measurement and shows all of those sizes together, so you do not need to search a separate chart for each garment.
How to use the chest size calculator
- Choose men (chest) or women (bust).
- Measure around the fullest part, under the arms and across the shoulder blades, tape horizontal.
- Enter the number in inches or centimetres.
- Read the sizes. For men: letter, jacket, EU, French and German suit sizes, T-shirt size. For women: letter and US, UK, EU numbers.
Chest size formula
French suit size = b ÷ 2 + 0.5 · German suit size = b ÷ 2 − 0.5 (b = chest in cm), rounded to even
letter size = Nike chart band
The letter bands are Nike’s tops charts; the European suit formulas and the T-shirt table are from Wikipedia’s Clothing sizes article (retrieved 2026-10-15). The French and German formulas give a different scale from the EU / Russia size derived from the UK and US sizes, so the calculator labels each clearly.
| Letter | Chest (in) | Chest (cm) |
|---|---|---|
| XXS | 28.1 – 31.5 | 71 – 80 |
| XS | 31.5 – 35 | 80 – 89 |
| S | 35 – 37.5 | 89 – 95 |
| M | 37.5 – 41 | 95 – 104 |
| L | 41 – 44 | 104 – 112 |
| XL | 44 – 48.5 | 112 – 123 |
| XXL | 48.5 – 53.5 | 123 – 136 |
| 3XL | 53.5 – 58 | 136 – 147 |
| 4XL | 58 – 63 | 147 – 160 |
Worked example
A man with a 40 in (101.6 cm) chest.
- Letter: M (chest 37.5–41 in). Jacket size 40, EU / Russia 50.
- French suit size: 101.6 ÷ 2 + 0.5 = 51.3, nearest even 52. German: 101.6 ÷ 2 − 0.5 = 50.3, nearest even 50.
- T-shirt EU size: 39/40 (M).
Reading the results
- Different scales: the French and German formulas are not the same as the EU / Russia list on the UK and US conversion. Use the one printed on the garment.
- Fit: a jacket should fit the chest and shoulders first; sleeves can be altered.
- Borderline: Nike advises the smaller size for a tighter fit or the larger for a looser fit.
- Women: bust sizes decide tops and dresses; hips and waist matter for bottoms.
See the T-Shirt Size Calculator, Suit Size Calculator and Clothing Size Converter (International) for more detail. This page gives general sizing guidance.
Sources
Every figure above comes from these pages, read directly on the dates shown. Brand names are used only to identify published charts.
- Nike — men’s tops size chart (chest) — checked 2026-10-15
- Nike — women’s tops size chart (bust, conversions) — checked 2026-10-15
- Wikipedia — Clothing sizes (men’s suits: EU, French and German formulas; T-shirts by chest girth) — checked 2026-10-15
Frequently asked questions
How do I measure my chest?
Wrap a tape around the fullest part of your chest, under the arms and across the shoulder blades, keeping it horizontal. Stand relaxed with your arms down and breathe normally. Women measure the bust the same way.
What chest size is a medium?
On Nike’s men’s chart a medium is a 37.5 to 41 inch chest (95 to 104 cm); a large is 41 to 44 inches. Women’s medium is a 35.5 to 38 inch bust.
How do the French and German suit sizes work?
Wikipedia gives the formulas: French size = chest in cm ÷ 2 + 0.5, German size = chest in cm ÷ 2 − 0.5. A 102 cm chest is about 51.5 in France and 50.5 in Germany; standard sizes are even, so the calculator rounds to the nearest even number.
Is the chest size the same as the jacket size?
For men yes, in inches rounded to an even number. A 43 inch chest takes a size 44 jacket. The EU / Russian size is 10 higher.
Where do waist and hips come in?
Use the Waist Size Calculator and Hip Size Calculator for trousers and skirts. For jackets see the Suit Size Calculator.