Length Converter
Convert between length units instantly — millimeters, centimeters, meters, kilometers, inches, feet, yards, and miles.
Result
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Calculated locally. Your numbers never leave your browser.
Common questions
Are the imperial conversions (inches, feet, miles) exact, or rounded approximations?
Exact — this uses the 1959 International Yard and Pound Agreement's precise definition (1 inch = 25.4mm exactly), so every imperial length unit here is derived from that one exact constant, not a separately rounded approximation.
How precise is the result shown?
Displayed to 8 significant figures, with ordinary floating-point noise cleaned up — so converting through a unit chain shows a clean number like 3.3 instead of something like 3.3000000000000003.