Speed Converter
Fast, accurate speed conversions, right in your browser.
The Speed Converter converts between mph, km/h, m/s, knots and other velocity units used across transportation, aviation, and maritime contexts — knots specifically remain standard in aviation and marine navigation even where the surrounding country uses metric units elsewhere.
How to Convert
- Enter your speed value and select the starting unit
- Choose your target unit
- The converted result appears instantly
Frequently Asked Questions
What speed units does this converter support?
Common units include kilometers per hour (km/h), miles per hour (mph), meters per second (m/s), and knots.
How do I convert mph to km/h?
Multiply the mph value by approximately 1.609 to get km/h.
What is a knot, and where is it used?
A knot equals one nautical mile per hour (about 1.15 mph), and is the standard speed unit used in maritime and aviation navigation.
Why do speedometers show different units in different countries?
The US and UK primarily use mph, while most other countries use km/h as part of the metric system — this converter helps compare speed limits or vehicle specs across regions.
Is this tool free to use?
Yes, completely free with no signup, no limits and no software to install.
Is my data saved anywhere?
No — conversions run in your browser and the values you enter are not stored or sent to a server.
How fast is the speed of sound in these units?
The speed of sound is roughly 1,235 km/h or 767 mph at sea level under standard conditions — useful as a reference point for high-speed conversions.
Is this useful for running or cycling pace comparisons?
For running/cycling pace specifically (time per distance, like minutes per mile), a dedicated pace converter is more appropriate — this tool handles standard speed (distance per time) units.
Can I convert meters per second to km/h?
Yes — multiply m/s by 3.6 to get km/h.
Is this useful for wind speed or weather data?
Yes — converting wind speed between mph, km/h, and knots is common when comparing forecasts from sources using different unit conventions.
