- Electronics: Many laptop screens have diagonal sizes listed in inches yet their actual width can be measured in millimeters.
- Carpentry: Woodworking often uses both systems so you may need to match a 540 mm board to an 21.26 inch standard.
- Fashion: Shoe lasts sometimes specify width in millimeters which can help find the right size abroad.
- Automotive: Parts such as filters or brackets listed with metric specs become actionable once converted.
| Millimeters | Inches |
|---|---|
| 100 | 3.94 |
| 300 | 11.81 |
| 540 | 21.26 |
| 610 | 24.02 |
| 800 | 31.50 |