mile per hour (mph)
1 mile per hour = 0.44704 metres per second
What is mile per hour?
Mile per hour is a unit of speed equal to one mile travelled in one hour. It is the standard unit for road speeds, vehicle performance ratings, and weather reports in the United States and United Kingdom.
Notes: Imperial/USCS unit
Real-world uses
Miles per hour is the standard speed unit for road traffic in the United States, the United Kingdom, and a few other countries. Baseball pitching speed, hurricane wind categories (Saffir-Simpson scale), and NASCAR race speeds are quoted in mph.
History
Miles per hour became the standard speed expression in English-speaking countries with the advent of railways and later automobiles. The first US speed limit (8 mph in New York City, 1901) and British speed cameras use mph as the legal standard.
Common mistakes
Assuming mph-to-km/h conversion is a simple ×1.5—the actual factor is 1.609. Also, forgetting that UK and US speed limits both use mph, which can mislead visitors from metric countries into driving too fast or too slow.
When is this conversion used?
Converting between mile per hour and metre per second is common when working across metric and imperial systems, such as international trade, travel between countries with different measurement standards, or following instructions from a different region. Speed limits, vehicle speedometers, and weather reports for wind speeds use different units depending on the country, making km/h to mph conversion one of the most practical speed conversions.
How to convert mile per hour to metre per second
To convert mile per hour to metre per second, multiply the value by 0.44704.
Conversion formula (from base unit)
x * 0.44704
Measurement standards
The SI unit of speed is metres per second (m/s), a derived unit requiring no independent definition. The knot is defined as exactly one nautical mile (1,852 metres) per hour and is sanctioned for maritime and aeronautical navigation by the International Civil Aviation Organization.
Did you know?
The fastest human-made object is the Parker Solar Probe, which reached 635,266 km/h (about 176 km/s) in 2024 during a close pass of the Sun — fast enough to travel from New York to Tokyo in under a minute.
| miles per hour | metres per second |
|---|---|
| 0.1 | 0.044704 |
| 0.5 | 0.22352 |
| 1 | 0.44704 |
| 2 | 0.89408 |
| 5 | 2.2352 |
| 10 | 4.4704 |
| 25 | 11.176 |
| 50 | 22.352 |
| 100 | 44.704 |
| 250 | 111.76 |
| 500 | 223.52 |
| 1,000 | 447.04 |
Common values
| miles per hour | metres per second | |
|---|---|---|
| Walking speed | 3.13171081 miles per hour | 1.4 metres per second |
| City speed limit | 31.09341446 miles per hour | 13.9 metres per second |
| Highway driving | 70.01610594 miles per hour | 31.3 metres per second |
| Commercial aircraft | 559.23407301 miles per hour | 250 metres per second |
| Speed of sound (sea level) | 761.20705082 miles per hour | 340.29 metres per second |
Full mile per hour conversion table
| Unit | Value | Factor |
|---|---|---|
| metre per second | 1 mph = 0.44704 m/s | × 0.44704 |
| kilometre per hour | 1 mph = 1.609344 km/h | × 1.609344 |
| knot | 1 mph = 0.86897624 kn | × 0.86897624 |
| foot per second | 1 mph = 1.46666667 ft/s | × 1.46666667 |
| metre per minute | 1 mph = 26.8224 m/min | × 26.8224 |
| kilometre per second | 1 mph = 0.00044704 km/s | × 0.00044704 |
| mach (approx at sea level) | 1 mph = 0.0013137 Ma | × 0.0013137 |
| centimetre per second | 1 mph = 44.704 cm/s | × 44.704 |
| mile per minute | 1 mph = 0.01666667 mi/min | × 0.01666667 |