How to use
- Type a number in Value.
- Pick the From and To units, or tap a popular conversion.
- Read the answer. It updates as you type.
How the conversion works
Every unit has an exact size in meters. The converter turns your value into meters, then into the unit you want:
result = value × (meters in "from" unit) ÷ (meters in "to" unit)
| Unit | Exact size |
|---|---|
| 1 inch | 2.54 cm |
| 1 foot | 12 in = 30.48 cm |
| 1 yard | 3 ft = 0.9144 m |
| 1 mile | 5,280 ft = 1,609.344 m |
| 1 nautical mile | 1,852 m |
These sizes are fixed by international agreement. The only rounding happens in the answer you see.
Examples
- 100 cm to inches: 100 ÷ 2.54 = 39.37 in
- 5 ft 9 in to cm: (5 × 12 + 9) × 2.54 = 175.26 cm
- A marathon in miles: 42.195 km ÷ 1.609344 = 26.22 mi
Conversion charts
| Centimeters | Inches |
|---|---|
| 1 cm | 0.3937 in |
| 5 cm | 1.9685 in |
| 10 cm | 3.937 in |
| 30 cm | 11.811 in |
| 50 cm | 19.685 in |
| 100 cm | 39.3701 in |
| Inches | Centimeters |
|---|---|
| 1 in | 2.54 cm |
| 2 in | 5.08 cm |
| 6 in | 15.24 cm |
| 12 in (1 ft) | 30.48 cm |
| 36 in (1 yd) | 91.44 cm |
| Feet | Meters |
|---|---|
| 1 ft | 0.3048 m |
| 3 ft | 0.9144 m |
| 5 ft | 1.524 m |
| 6 ft | 1.8288 m |
| 10 ft | 3.048 m |
| Kilometers | Miles |
|---|---|
| 1 km | 0.6214 mi |
| 5 km | 3.1069 mi |
| 10 km | 6.2137 mi |
| 21.0975 km (half marathon) | 13.1094 mi |
| 42.195 km (marathon) | 26.2188 mi |
More detail: special units
- US survey foot: 1200/3937 m, about 2 parts per million longer than the normal foot. NIST retired it on 1 January 2023. It is listed only for old survey records.
- Light-year: the distance light travels in a year of 365.25 days, as defined by the International Astronomical Union.
- A4 paper: 210 × 297 mm, about 8.27 × 11.69 inches.
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