Popular speed conversions
- Kilometers per hour to miles per hour1 km/h = 0.621371 mph
- Kilometers per hour to meters per second1 km/h = 0.277778 m/s
- Kilometers per hour to knots1 km/h = 0.539957 kn
- Kilometers per hour to feet per second1 km/h = 0.911344 ft/s
- Miles per hour to kilometers per hour1 mph = 1.60934 km/h
- Miles per hour to meters per second1 mph = 0.44704 m/s
- Miles per hour to knots1 mph = 0.868976 kn
- Miles per hour to feet per second1 mph = 1.46667 ft/s
- Meters per second to kilometers per hour1 m/s = 3.6 km/h
- Meters per second to miles per hour1 m/s = 2.23694 mph
- Meters per second to knots1 m/s = 1.94384 kn
- Meters per second to feet per second1 m/s = 3.28084 ft/s
- Knots to kilometers per hour1 kn = 1.852 km/h
- Knots to miles per hour1 kn = 1.15078 mph
- Knots to meters per second1 kn = 0.514444 m/s
- Knots to feet per second1 kn = 1.68781 ft/s
- Feet per second to kilometers per hour1 ft/s = 1.09728 km/h
- Feet per second to miles per hour1 ft/s = 0.681818 mph
- Feet per second to meters per second1 ft/s = 0.3048 m/s
- Feet per second to knots1 ft/s = 0.592484 kn
- Mach to kilometers per hour1 Ma = 1,225.04 km/h
- Kilometers per hour to Mach1 km/h = 0.000816297 Ma
- Mach to miles per hour1 Ma = 761.207 mph
- Miles per hour to Mach1 mph = 0.0013137 Ma
About speed units
Speed is distance per unit time, so every speed unit is a length unit divided by a time unit. Converting km/h to m/s means dividing by 3.6; one mile per hour is exactly 0.44704 m/s; one knot is one nautical mile per hour (exactly 1,852/3,600 m/s).
Speed unit reference
| Unit | Symbol | Value in m/s | System |
|---|---|---|---|
| Meter per second | m/s | 1 m/s | SI |
| Kilometer per hour | km/h | 0.27777778 m/s | Metric |
| Mile per hour | mph | 0.44704 m/s | US customary |
| Knot | kn | 0.51444444 m/s | Other |
| Foot per second | ft/s | 0.3048 m/s | US customary |
| Foot per minute | ft/min | 0.00508 m/s | US customary |
| Inch per second | in/s | 0.0254 m/s | US customary |
| Centimeter per second | cm/s | 0.01 m/s | SI |
| Meter per minute | m/min | 0.016666667 m/s | Metric |
| Kilometer per second | km/s | 1,000 m/s | SI |
| Mach (ISA sea level) | Ma | 340.29 m/s | Other |
| Speed of light | c | 299,792,460 m/s | Other |
Frequently asked questions
What is the SI unit of speed?
This converter uses the meter per second (m/s) as its reference unit; every other unit is defined relative to it.
How many speed units can I convert?
12 units are supported here, across SI, Metric, US customary, Other systems. Every pair can be converted in both directions.
Does this speed converter work offline?
Yes. Once the page has loaded, every calculation runs locally in your browser — nothing is sent to a server.