Content reviewed: 24 September 2026

Converting length through a common base unit

The converter stores each supported unit as a scale relative to metres. Your input is first converted to metres and then from metres to the target unit. This keeps conversions consistent across metric and imperial choices.

Examples of exact conversion factors

1 km = 1,000 m
1 in = 0.0254 m
1 ft = 0.3048 m
1 yd = 0.9144 m
1 mi = 1,609.344 m

Example

To convert 10 miles to kilometres, the calculator converts 10 × 1,609.344 metres, then divides by 1,000. The result is 16.09344 km.

Precision and rounding

The underlying conversion factors can be more precise than the number of decimal places you need for a practical task. Round the displayed result according to the measurement precision required for engineering, construction, schoolwork or everyday use.

For a broader explanation of unit factors and dimensional checks, read the Unit Conversion Guide.