About this calculator
Type a number, choose the unit you have and the unit you want, and this converter gives you the answer at once, along with the same length and distance in every other unit it knows.
Every conversion factor is exact by definition wherever one exists, and each result shows the working so you can check it.
Worked examples
Real numbers, worked out by the same calculator. Press “Use these numbers” to try one above.
1 mi to km
- kilometres (km)
- 1.609344 km
- metres (m)
- 1,609.344 m
- centimetres (cm)
- 160,934.4 cm
- millimetres (mm)
- 1,609,344 mm
- micrometres (µm)
- 1,609,344,000 µm
- nanometres (nm)
- 1,609,344,000,000 nm
- yards (yd)
- 1,760 yd
- feet (ft)
- 5,280 ft
- inches (in)
- 63,360 in
- nautical miles (nmi)
- 0.868976241901 nmi
1 mi is 1.609344 km.
Show the working
- Change to the base unit (m): 1 mi × 1,609.344 = 1,609.344 m.
- Change to km: 1,609.344 ÷ 1,000 = 1.609344 km.
6 ft to m
- metres (m)
- 1.8288 m
- kilometres (km)
- 0.0018288 km
- centimetres (cm)
- 182.88 cm
- millimetres (mm)
- 1,828.8 mm
- micrometres (µm)
- 1,828,800 µm
- nanometres (nm)
- 1,828,800,000 nm
- miles (mi)
- 0.00113636363636 mi
- yards (yd)
- 2 yd
- inches (in)
- 72 in
- nautical miles (nmi)
- 0.00098747300216 nmi
6 ft is 1.8288 m.
Show the working
- Change to the base unit (m): 6 ft × 0.3048 = 1.8288 m.
- Change to m: 1.8288 ÷ 1 = 1.8288 m.
100 m to yd
- yards (yd)
- 109.361329834 yd
- kilometres (km)
- 0.1 km
- centimetres (cm)
- 10,000 cm
- millimetres (mm)
- 100,000 mm
- micrometres (µm)
- 100,000,000 µm
- nanometres (nm)
- 100,000,000,000 nm
- miles (mi)
- 0.0621371192237 mi
- feet (ft)
- 328.083989501 ft
- inches (in)
- 3,937.00787402 in
- nautical miles (nmi)
- 0.0539956803456 nmi
100 m is 109.361329834 yd.
Show the working
- Change to the base unit (m): 100 m × 1 = 100 m.
- Change to yd: 100 ÷ 0.9144 = 109.361329834 yd.
How to convert by hand
Every length unit is a fixed fraction or multiple of the metre. To convert, multiply by the size of the unit you have (in metres), then divide by the size of the unit you want. For example, to change 6 feet to metres, multiply by 0.3048: 6 × 0.3048 = 1.8288 m. To go back, divide by 0.3048.
Since 1959 the inch has been defined as exactly 25.4 millimetres, and everything else in the imperial system (foot, yard, mile) follows from it exactly: 12 inches make a foot, 3 feet make a yard and 1,760 yards make a mile.
Conversion factors used
Each unit is stored as its size in m. The sizes below are the ones this converter uses.
| Unit | Size |
|---|---|
| metres (m) | 1 m |
| kilometres (km) | 1,000 m |
| centimetres (cm) | 0.01 m |
| millimetres (mm) | 0.001 m |
| micrometres (µm) | 0.000001 m |
| nanometres (nm) | 1e-9 m |
| miles (mi) | 1,609.344 m |
| yards (yd) | 0.9144 m |
| feet (ft) | 0.3048 m |
| inches (in) | 0.0254 m |
| nautical miles (nmi) | 1,852 m |
Common conversions
| From | To |
|---|---|
| 1 in | 2.54 cm |
| 1 ft | 30.48 cm |
| 1 yd | 0.9144 m |
| 1 mi | 1.609344 km |
| 1 nmi | 1.852 km |
| 100 m | 328.083989501 ft |
| 5 km | 3.10685596119 mi |
| 10 cm | 3.93700787402 in |
Miles, nautical miles and feet
A statute mile is 5,280 feet (1,609.344 m). A nautical mile is longer, at exactly 1,852 m, because it is based on one minute of latitude; ships and aircraft measure distance in nautical miles and speed in knots (nautical miles per hour).
Frequently asked questions
How many feet are in a mile?
There are 5,280 feet in a statute mile.
How many inches are in a metre?
A metre is about 39.37 inches (1 ÷ 0.0254 = 39.3700787…).
What is the difference between a mile and a nautical mile?
A mile is 1,609.344 m. A nautical mile is 1,852 m, about 15% longer, and is used at sea and in the air.
How accurate is this converter?
It uses the exact defined factors wherever they exist and shows up to 12 significant digits, so the results are accurate to far more digits than you will normally need.
Formulas tested against hand-worked answers. Last reviewed 29 September 2026. These calculators do arithmetic only; they are not financial, tax or legal advice.