Speed Converter
Convert between mph, km/h, knots, m/s and Mach with common reference speeds for walking, cycling and motorway driving
Closest Reference Speed
70 mph = Motorway
All Conversions
mph
70.00
km/h
112.65
knots
60.83
m/s
31.29
Mach
0.05
Common Speeds
Walking speed
1.4 mph
2.3 km/h
Running pace
6 mph
9.7 km/h
Cycling
20 mph
32.2 km/h
Car (city)
50 mph
80.5 km/h
Motorway
70 mph
112.7 km/h
Train (express)
100 mph
160.9 km/h
Aeroplane
300 mph
482.8 km/h
Speed of sound
767 mph
1234.4 km/h
mph: miles per hour (US/UK). km/h: kilometres per hour (metric). knots: used in aviation and maritime. m/s: metres per second (physics/science). Mach: speed of sound (aviation).
Common Speed Units
Different contexts use different speed units: car driving (mph, km/h), maritime (knots), aviation (knots, Mach), athletics (m/s, km/h, mph), space (km/s). Convert between any pair: 1 mph = 1.609 km/h = 0.869 knots = 0.447 m/s. 1 km/h = 0.621 mph = 0.540 knots = 0.278 m/s.
Reference speeds: walking pace = 3 mph = 4.83 km/h = 1.34 m/s. Running pace = 6-12 mph. Highway driving = 60-80 mph = 96-129 km/h. Commercial jet cruise = 540 mph = 870 km/h = 469 knots = 240 m/s = Mach 0.78. Speed of sound at sea level = 767 mph = 1,235 km/h = 343 m/s = Mach 1.
Common Speed Conversions
| mph | km/h | knots | m/s |
|---|---|---|---|
| 1 | 1.61 | 0.87 | 0.45 |
| 10 | 16.09 | 8.69 | 4.47 |
| 30 | 48.28 | 26.07 | 13.41 |
| 60 | 96.56 | 52.14 | 26.82 |
| 80 | 128.75 | 69.52 | 35.76 |
| 100 | 160.93 | 86.90 | 44.70 |
| 200 | 321.87 | 173.79 | 89.41 |
| 500 | 804.67 | 434.49 | 223.52 |
Frequently Asked Questions
Why so many speed units?
Different industries developed independently. Maritime and aviation share knots tradition. Cars/road use mph (US/UK) or km/h (rest of world). Physics uses m/s. Space speed in km/s. Each unit suits its domain - converting is mostly a cross-context need.
Is mph or km/h faster?
Same speed in different units. The number on a US speedometer (mph) is smaller than the same speed in km/h (UK/EU). 60 mph = 97 km/h. So 60 'feels' slower in mph - same actual speed, different displayed number.
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