Coat Size Calculator: Built for Layering
This coat size calculator factors the heavy-layer allowance most online buyers miss. A $400 coat is painful to return; get the size right first time by entering your chest measurement plus layer count (light, mid, heavy). The tool returns sizes for trench, peacoat, parka, and overcoat styles in US, UK, EU. Use the calculator below to get your exact fit in 30 seconds.
How it works
Measure yourself
Take your bust, waist, and hips with a soft tape. See the full measurement guide.
Enter the numbers
Type your measurements into the calculator above. Pick inches or cm — the tool converts both ways.
Get your size
Match the result against the brand's chart and order with confidence.
Men's tops — chest-driven sizing
| Size | US | UK | EU | Chest |
|---|---|---|---|---|
| XS | 34 | 34 | 44 | 32–34" |
| S | 36 | 36 | 46 | 35–37" |
| M | 38–40 | 38–40 | 48–50 | 38–40" |
| L | 41–43 | 41–43 | 52–54 | 41–43" |
| XL | 44–46 | 44–46 | 56–58 | 44–46" |
| XXL | 47–49 | 47–49 | 60–62 | 47–49" |
Frequently Asked Questions
How much extra room do I need in a winter coat?
1.5–2 inches of chest ease for a sweater layer; 3–4 inches for a heavy fleece + sweater. The calculator's layer mode handles this.
Should I size up for a parka?
Parkas are designed with layering room already built in. Match the calculator's number rather than adding more.
How do I measure for a trench coat?
Measure your chest over a shirt (no sweater). Trench coats are typically worn over light layers and aren't built for heavy bulk underneath.
What if a coat fits the chest but is too long?
Coats can be hemmed at the bottom for $30–60. Sleeves are harder to shorten because of the cuff structure — match sleeve length carefully on the size chart.
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