Button Size Chart: Ligne to mm, cm and Inches Conversion Table
Looking up a button size? This chart converts every common button size between ligne (L), millimetres, centimetres and inches — bookmark it for quick reference. The rule behind it all: 1 ligne = 0.635 mm (1/40 inch), so ligne × 0.635 = mm.
Button size conversion chart
| Ligne | mm | cm | Inches | Typical use |
|---|---|---|---|---|
| 14L | 8.9 mm | 0.89 cm | 0.35" | Shirt collars & cuffs |
| 16L | 10.2 mm | 1.02 cm | 0.40" | Shirt collars & sleeve plackets |
| 18L | 11.4 mm | 1.14 cm | 0.45" | Dress shirt front (standard) |
| 20L | 12.7 mm | 1.27 cm | 0.50" | Blouses, light shirts |
| 22L | 14.0 mm | 1.40 cm | 0.55" | Blouses, dresses |
| 24L | 15.2 mm | 1.52 cm | 0.60" | Blazer sleeves, cardigans |
| 27L | 17.1 mm | 1.71 cm | 0.67" | Jeans tack buttons |
| 28L | 17.8 mm | 1.78 cm | 0.70" | Trousers, skirts, knitwear |
| 30L | 19.1 mm | 1.91 cm | 0.75" | Jackets, heavier knitwear |
| 32L | 20.3 mm | 2.03 cm | 0.80" | Suit & blazer front (standard) |
| 34L | 21.6 mm | 2.16 cm | 0.85" | Jackets, light coats |
| 36L | 22.9 mm | 2.29 cm | 0.90" | Coats |
| 40L | 25.4 mm | 2.54 cm | 1.00" | Overcoat front (standard) |
| 44L | 27.9 mm | 2.79 cm | 1.10" | Heavy overcoats, statement buttons |
Want to see these sizes at their true scale on your screen? Open our Button Size Visualizer — every size drawn at real diameter, calibrated to your display. For converting any value not in the chart, use the size converter.
Standard button sizes by garment
| Garment | Ligne | mm |
|---|---|---|
| Shirt collar & cuffs | 14–16L | 8.9–10.2 mm |
| Shirt & blouse front | 18L | 11.4 mm |
| Blazer sleeve | 24L | 15.2 mm |
| Blazer & suit front | 32L | 20.3 mm |
| Trousers & skirt waistband | 24–28L | 15.2–17.8 mm |
| Jeans (tack button) | 27L | 17.1 mm |
| Cardigan & knitwear | 24–28L | 15.2–17.8 mm |
| Coat & overcoat front | 40–44L | 25.4–27.9 mm |
How are buttons measured?
A button's size is its diameter measured straight across the middle, edge to edge. The ligne system (from the French for "line") has been the trade standard since the 18th century. To measure a button you already have: lay it flat and measure across the widest point in millimetres, then find the closest match in the chart above.
Not sure which size is right for your project? That's a judgement call rather than a lookup — see our full guide to choosing button sizes.
Shop by size
All our buttons are listed with both ligne and mm sizes. Browse shirt buttons (14–18L), suit & blazer buttons (24–32L), cardigan buttons (24–28L) or coat buttons (32–44L) — from €0.23 per button, no minimum order.