Distance Converter
Convert any distance between metric, imperial, nautical and astronomical units instantly.
From
To
- 1
Convert to the base unit
1 km × 1,000 = 1,000 - 2
Convert to the target unit
1,000 ÷ 1,609.344 = 0.621371 mi
1 km =
| Nanometer | 999,999,999,999.9999 nm |
| Micrometer (micron) | 1,000,000,000 µm |
| Millimeter | 1,000,000 mm |
| Centimeter | 100,000 cm |
| Meter | 1,000 m |
| Inch | 39,370.07874 in |
| Foot | 3,280.839895 ft |
| Yard | 1,093.613298 yd |
How this is calculated
Every distance unit is stored as a fixed ratio to the metre — the SI base unit for length. To convert, the input is first multiplied by the source unit's "metres per unit" factor to obtain a value in metres, then divided by the target unit's factor: result = value × (from_factor / to_factor). These ratios are exact international definitions (e.g. 1 inch = 0.0254 m exactly, 1 foot = 0.3048 m, 1 mile = 1609.344 m, 1 nautical mile = 1852 m). Larger astronomical units use IAU-accepted values: 1 AU = 149 597 870 700 m (exact, 2012 IAU resolution) and 1 light-year ≈ 9.461 × 10¹⁵ m (Julian year basis).
Because distance has no offset (unlike temperature), every conversion is a pure multiplication and the operation is perfectly reversible. The only practical limitation is floating-point precision for very large or very small values — converting nanometres to light-years, for example, can lose significance beyond ~15 significant digits.
Frequently asked questions
One kilometre equals approximately 0.621371 miles. One mile equals exactly 1.609344 kilometres.
A nautical mile is exactly 1852 metres. It is used in aviation and maritime navigation and equals approximately 1.15078 statute miles.
One light-year is about 9.461 × 10¹² kilometres — the distance light travels in one Julian year (365.25 days) at ~299,792 km/s.
Also known as
TG we-Calculate Editorial Team. (2026). Distance Converter [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/distance-converter
TG we-Calculate Editorial Team. "Distance Converter." TG we-Calculate. 2026. https://we-calculate.com/calculator/distance-converter.
TG we-Calculate Editorial Team, "Distance Converter," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/distance-converter
@misc{wecalculate_distance_converter, title = {Distance Converter}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/distance-converter}}, year = {2026}, note = {TG we-Calculate} }
Did this calculator help you?