kilometer per hour to mile per hour converter

Convert kilometer per hour to mile per hour in the Speed family. See a sample calculation, unit definitions, and the interactive converter.

Example conversion: 1 km-h

0.6213711922 mile per hour

This example is calculated from the same unit registry used by the interactive converter.

Formula and unit definitions

Convert linear speeds used in transport, sport, navigation and science.

target value = source value × source factor ÷ target factor

Source unit: kilometer per hour (km-h), factor 0.2777777778, offset 0.

Target unit: mile per hour (mph), factor 0.44704, offset 0.

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Important note

The calculation is performed locally from the listed unit definitions. Display results are rounded for readability; high-precision and regulated work should use the governing standard and appropriate significant figures.

For high-precision, regulated or safety-critical use, check the underlying standard and its required precision. Historical and approximate units are identified in their names or family descriptions.

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