Speed Converter

Speed Converter online tool

Use this free online speed converter to easily convert between units for measuring speed (magnitude of velocity). Metric and imperial units for measuring speed are supported.

Speed conversion. Imperial vs. Metric units.

Since 1959 both metric and imperial units of speed are defined using the standard meter (metre in British English) as a base unit. Consequently, all metric units for measuring velocity are expressed relative to it, e.g. a kilometer is 1,000 meters. To convert between metric units one needs to take into account the length dimension and the time dimension. E.g. in converting meters per second to km per hour, you need to multiply by 3600 to account for the 3600 seconds in an hour, and also divide by 1,000 to account for the length dimension, resulting in a multiplication by 3.6 (see more examples below). The same logic of conversion applies to conversions from one imperial unit to another, with both dimensions taken into account.

Imperial units can trace their lineage further back in history but are currently in official use only in the United States, United Kingdom, and a couple of other countries, while the metric system is official in the rest of the world. Using a speed converter can be considered one way to bring these countries closer together, as it doesn't seem either side is willing to forgo its speed unit system.

When converting from metric to imperial or from imperial to metric units of speed, the logic is the same, only the multiplication or division factor is different. Since all imperial units are defined in terms of the meter, the conversions are exact and not approximate, as can be the case with a few fringe measurement units in other areas.