Written by Muneeb Rana · Last updated 26 October 2026
Quick answer: What does mph mean? It stands for miles per hour: how many miles you would cover in one hour at a steady speed. A car at 60 mph travels one mile per minute. It is the road-speed unit in the US and UK. One mph equals exactly 1.609344 km/h or about 0.447 metres per second.
TL;DR
- mph = miles per hour.
- 60 mph = 1 mile per minute.
- 1 mph = 1.609344 km/h.
- 1 mph ≈ 0.447 m/s.
- Used for road signs in the US and UK.
What does mph mean in practice
At 30 mph you cover half a mile each minute; at 60 mph, a mile each minute. It is a rate, not a distance.
Everyday speeds
| Activity | Typical mph |
|---|---|
| Walking | about 3 |
| Jogging | 5–6 |
| Cycling (casual) | 10–12 |
| Town driving | 20–30 |
| Motorway | 60–70 |
| Airliner cruise | 500+ (ground speed varies) |
Rough illustrations; see linked guides for sources.
History
The mile has Roman roots; the international mile was fixed at 1,609.344 m in 1959. Wikipedia's mph article covers usage.
Converting
mph × 1.609344 = km/h; mph × 0.44704 = m/s; mph ÷ 1.150779 = knots. Tools: mph to km/h, mph to m/s.
On your speedometer
Car speedometers in the US and UK show mph prominently, with km/h on an inner scale. Speedometer PRO shows MPH or KM/H.
Where the mile comes from
The mile comes from the Roman mille passus, a thousand paces. The international mile used today is defined as exactly 1,609.344 metres, fixed by international agreement in 1959. That is why conversions between mph and km/h use the factor 1.609344.
Who uses mph
Road signs in the United States and the United Kingdom show limits in mph, along with a few other countries and territories. Most of the world uses km/h. Aviation and shipping use knots. If you drive abroad, check which unit the signs use before setting off.
Reading mph quickly
A useful mental trick: to turn mph into km/h, multiply by 1.6 (60 mph ≈ 96 km/h). To go the other way, multiply km/h by 0.62 (100 km/h ≈ 62 mph).
Other uses of miles
The nautical mile (1,852 m) and the old US survey mile differ from the international mile. Road mph always uses the international mile.
Writing it correctly
Write "mph" in lower case with no full stops in most style guides; "MPH" is common on signs and displays.
Read next
Related: MPH guide: speed units explained · MPH vs km/h · MPH to KMH converter · MPH to meters per second converter · Speedometer MPH and KM/H units · Average walking speed · KMH to MPH converter · Knots to MPH converter
Get Speedometer PRO on Google Play · Download on the App Store · Set it up before you move; never handle your phone while driving.
Sources
- Miles per hour (Wikipedia): en.wikipedia.org (accessed 26 October 2026)
- Unit conversion (NIST Office of Weights and Measures): nist.gov (accessed 26 October 2026)
- Speed (Wikipedia): en.wikipedia.org (accessed 26 October 2026)
- Mile (Wikipedia): en.wikipedia.org (accessed 26 October 2026)
FAQ
What does mph stand for?
Miles per hour.
How fast is 60 mph?
One mile per minute, or about 96.6 km/h.
Is mph the same as m/h?
No. 'm/h' is ambiguous; mph means miles per hour, while m/s is metres per second.
Who uses mph?
Mainly the United States and the United Kingdom for road speeds.
How many km/h is 1 mph?
Exactly 1.609344 km/h.