Speed Converter
Sixty miles per hour is 96.6 km/h, 26.8 metres per second and 52.1 knots. Same speed, five ways of saying it.
Converted
96.560640km per hour
- metres per second
- 26.822400
- km per hour
- 96.560640
- miles per hour
- 60.000000
- knots
- 52.138575
- feet per second
- 88.000000
- Conversions use the defined factors rather than the rounded ones people memorise. An inch is exactly 25.4 millimetres by international agreement, not 25 and a bit, so these will not drift.
- Every unit in the family is shown, not just the one you asked for, because the next question is usually a different one.
About speed conversion
Speed is a distance over a time, so converting one means converting both parts. Everything here routes through metres per second, which is the scientific standard and the one physics formulas expect.
The knot is the odd one and the most interesting. It is one nautical mile per hour, and a nautical mile was originally one minute of latitude — one sixtieth of a degree along a meridian. That makes it 1,852 metres exactly by modern definition, and it is why navigators use it: a degree of latitude is sixty nautical miles, so distance on a chart reads straight off the latitude scale.
Metres per second is worth knowing for anything involving physics, because it is the unit every equation assumes. Kinetic energy, momentum and stopping distance all produce nonsense if fed km/h. Converting is straightforward: divide km/h by 3.6.
Two rough conversions are useful in the head. Multiply mph by 1.6 for km/h, and divide km/h by 3.6 for metres per second. Both are close enough for judgement and neither is exact.
What it works out
- mph, km/h, m/s, knots and ft/s
- Every unit shown at once
- Exact factors, including the nautical mile
The formula
Converted = Value × (m/s per from-unit) ÷ (m/s per to-unit)
Sixty miles per hour is 26.8224 metres per second, because a mile per hour is 0.44704 m/s. Dividing by the 0.2778 m/s in a km/h gives 96.56 km/h.
Sixty mph is also exactly 88 feet per second, which is a genuinely useful number — it means a car at 60 covers nearly the length of a tennis court every second, and it puts reaction times into perspective.
The knot works out at 52.14 for the same speed. A knot is one nautical mile an hour, and a nautical mile is 1,852 metres — about fifteen per cent longer than a statute mile.
For mental arithmetic: mph times 1.6 gives km/h, and km/h divided by 3.6 gives metres per second. The second one is exact, since there are exactly 3.6 thousand metres in a kilometre-hour.
- m/s
- The base unit. What physics equations expect.
- Knot
- One nautical mile per hour — 1,852 metres per hour exactly.
- 3.6
- Divides km/h into m/s exactly, since 1 km/h is 1000m over 3600s.
A worked example
Sixty miles per hour in kilometres per hour.
That works out to 96.560640 km per hour.
- metres per second
- 26.822400
- km per hour
- 96.560640
- miles per hour
- 60.000000
- knots
- 52.138575
- feet per second
- 88.000000
Questions
How many km/h is 60 mph?
96.56 km/h. The rough conversion of multiplying by 1.6 gives 96, which is close enough for reading a speed limit sign.
How do I convert km/h to m/s?
Divide by 3.6. It is exact, because a kilometre per hour is 1,000 metres over 3,600 seconds. One hundred km/h is 27.78 m/s.
What is a knot?
One nautical mile per hour, where a nautical mile is exactly 1,852 metres — about 15% longer than a statute mile. A knot is 1.852 km/h.
Why do ships and aircraft use knots?
Because a nautical mile is one minute of latitude, so sixty of them make a degree. Distance reads straight off the latitude scale on a chart, which mattered enormously before satellite navigation.
How fast is 60 mph in feet per second?
Exactly 88. A car at 60 mph covers 88 feet every second, which is a useful way to think about stopping distances and reaction times.
Why do physics problems use metres per second?
Because every equation assumes SI units. Feeding km/h into a kinetic energy or momentum calculation gives an answer wrong by a factor of about thirteen.