Rope Diameter Converter
Convert between rope diameter in mm and inches, plus circumference measurements.
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Rope is measured by its diameter or circumference.
Diameter conversions:
- 1 inch = 25.4 mm (exact)
- 1 mm = 0.03937 inches
Circumference from diameter:
- Circumference = diameter × π (3.14159)
- Diameter = circumference / π
Common rope sizes:
| Diameter (mm) | Diameter (in) | Circumference (mm) |
|---|---|---|
| 6 mm | 1/4" | 18.8 mm |
| 10 mm | 3/8" | 31.4 mm |
| 12 mm | 1/2" | 37.7 mm |
| 16 mm | 5/8" | 50.3 mm |
| 20 mm | 3/4" | 62.8 mm |
| 24 mm | 1" | 75.4 mm |
Older maritime systems measure rope by circumference rather than diameter.