Kilometres to Metres Converter
Convert kilometres to metres — multiply by a thousand. Results update as you type; exact factors shown.
One kilometre is 1,000 metres — see the exact factor, not a rounded rule of thumb.
How the kilometres to metres converter works
Every length is converted through the metre, the SI base unit of length. The inch has been defined as exactly 25.4 mm since the 1959 international yard and pound agreement, so a foot is exactly 0.3048 m, a yard 0.9144 m and a statute mile 1,609.344 m. The nautical mile is 1,852 m by international definition.
The UK is metric for most trade and science but keeps miles, pints, stone and mpg (with the imperial gallon) in daily life.
Common length conversions
| From | To | Units |
|---|---|---|
| 0.1 km | 100 m | kilometres to metres |
| 0.4 km | 400 m | kilometres to metres |
| 0.5 km | 500 m | kilometres to metres |
| 1 km | 1,000 m | kilometre to metres |
| 1.6 km | 1,600 m | kilometres to metres |
| 2 km | 2,000 m | kilometres to metres |
| 5 km | 5,000 m | kilometres to metres |
| 10 km | 10,000 m | kilometres to metres |
| 21.0975 km | 21,097.5 m | kilometres to metres |
| 42.195 km | 42,195 m | kilometres to metres |
| 100 km | 100,000 m | kilometres to metres |
| 1,000 km | 1,000,000 m | kilometres to metres |
Units in this converter and their exact factors
| Unit | Symbol | One unit in metres |
|---|---|---|
| millimetre | mm | 0.001 metre |
| centimetre | cm | 0.01 metre |
| metre | m | 1 metre |
| kilometre | km | 1,000 metre |
| inch | in | 0.0254 metre |
| foot | ft | 0.3048 metre |
| yard | yd | 0.9144 metre |
| mile | mi | 1,609.344 metre |
| nautical mile | nmi | 1,852 metre |
FAQFrequently asked questions about length conversion
How many metres in a kilometre?
Exactly 1,000.
What is a marathon in metres?
42,195 m — the distance is defined exactly.
What is 400 m?
0.4 km — one lap of a standard athletics track.
What is 1 km in miles?
0.621 miles.
What is a myriametre?
An obsolete unit of 10 km. It appears in old French and German texts.
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Physical Laboratory (NPL) — United Kingdom's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.