Numbers & units / length
Length units
Metric, imperial, nautical, and astronomical lengths. Type a value into any field; the rest update live.
live conversion
§ 01
Metric
Millimetermm
Centimetercm
Meterm
Kilometerkm
§ 02
Imperial
Inchin
Footft
Yardyd
Milemi
§ 03
Nautical & astronomical
Nautical milenmi
Astronomical unitau
Light yearly
How it works
Each unit is normalized to meters, then converted out to every other unit. Number formatting is auto-tuned to magnitude (more decimals for tiny values, scientific notation for huge ones).
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Tip
Click any field to copy its value. The light-year and astronomical-unit conversions are exact (IAU definitions).