CALCS

Conversion

Length converter

Enter a value in any length unit (metric or imperial) and see the equivalent in every other supported unit at once. Useful for travel, construction, fitness, and quick metric-to-imperial sanity checks.

Millimeters
1000
mm
Centimeters
100
cm
Kilometers
0.001
km
Inches
39.370079
in
Feet
3.2808399
ft
Yards
1.0936133
yd
Miles
0.00062137119
mi
Nautical miles
0.0005399568
nmi

Formula

Each unit has a fixed conversion factor to meters. The ratio of two factors gives the direct from→to conversion.

All conversions use exact international definitions: 1 inch ≡ 2.54 cm, 1 foot = 12 inches, 1 yard = 3 feet, 1 mile = 5280 feet, 1 nautical mile = 1852 meters (by international convention since 1929). The meter itself has been defined since 1983 as the distance light travels in vacuum in 1/299,792,458 of a second.

Results are computed in meters as an intermediate step and round-trip-safe — converting from feet to miles to feet gives back the original number exactly (up to floating-point precision). The display shows ~8 significant figures and switches to scientific notation for very large or very small values.

Examples

  1. 015 km in miles
    5 × 1000 ÷ 1609.344 ≈ 3.106856 mi
  2. 026 ft in cm
    6 × 30.48 = 182.88 cm
  3. 031 mile in feet
    1 × 1609.344 ÷ 0.3048 = 5280 ft (exact)
  4. 041 nautical mile in km
    1 × 1852 ÷ 1000 = 1.852 km (exact)

FAQ

  • Nautical miles correspond to one minute of latitude (1/60 of a degree along Earth's circumference). The historical statute mile derives from Roman 1000 paces ('mille passus'). Today nautical miles are standardized at exactly 1852 m to align with the metric system.

References

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