OTHER · LENGTH CONVERTER
Length Converter Calculator
Convert between millimetres, centimetres, metres, kilometres, inches, feet, yards, miles, and nautical miles. Uses exact NIST-defined conversion factors.
0.3048
m
1 ft = 0.3048 m
About This Calculator
Convert any length measurement between metric and imperial units instantly. All factors are exact per the 1959 international agreement (1 inch = 25.4 mm exactly).
How It Works
Select a source unit and a target unit, then enter your measurement. The converter multiplies your value by the source unit's factor relative to a canonical metre base, then divides by the target unit's factor — no approximation involved.
The Formula
result = value × factor(from) ÷ factor(to), where each factor is the unit's exact size in metres (e.g. 1 ft = 0.3048 m; 1 in = 0.0254 m).
Frequently Asked Questions
- How many metres are in a mile?
- Exactly 1609.344 metres — derived from 5280 feet × 0.3048 m/ft, both exact definitions.
- What is the difference between a nautical mile and a statute mile?
- A nautical mile is exactly 1852 m; a statute mile is 1609.344 m. Nautical miles follow the BIPM definition and are used in navigation.