Length Converter
Convert between metric and imperial length units instantly.
Overview
Length conversion between metric and imperial rests on one exact definition: the inch has been exactly 25.4 millimetres since the 1959 international yard and pound agreement. Every other factor follows — a foot is 0.3048 m, a yard 0.9144 m, and a statute mile 1,609.344 m — so these are definitions rather than measurements and carry no rounding error.
Resultado
All Conversions
| Unidade | Valor |
|---|---|
Click a row to set it as the target unit.
Conversion Factors (base: meter)
- 1 mm = 0.001 m
- 1 cm = 0.01 m
- 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
How to Use
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1
Enter the value
Type the amount you want to convert into the Length Converter.
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2
Choose the units
Select the unit to convert from and the unit to convert to.
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3
Read the converted value
The conversion updates instantly in your browser — no button, nothing sent to a server.
About
Before 1959 the United States and the Commonwealth used slightly different inches, differing in the eighth decimal place. The discrepancy was irrelevant at human scale but material in geodesy, which is why the US survey foot was retained for land surveying until its official retirement at the end of 2022.
Unit confusion remains expensive. The Mars Climate Orbiter was lost in 1999 when one team supplied thrust data in pound-force seconds while the receiving system expected newton-seconds, a reminder that conversion errors survive review when both figures look plausible.