Speed Converter
mph, km/h, knots, m/s and pace per mile.
Reviewed by the Calculation Machine team · Updated 24 October 2026 · How we check our maths
Your values
ⓘ Live results
- Miles per hour
- 60
- Kilometres per hour
- 96.5606
- Metres per second
- 26.8224
- Knots
- 52.1386
- Pace per mile
- 1:00
Quick answer
To convert speed, multiply mph by 1.609344 to get km/h, divide km/h by 3.6 to get meters per second, and divide km/h by 1.852 to get knots. All three factors are exact definitions. For example, 100 km/h is 62.14 mph, 27.78 m/s or 54.0 knots.
What the Speed Converter does
Type a speed in miles per hour, kilometers per hour, meters per second, knots or feet per second and this converter shows the other units together, plus the matching pace per mile — the minutes it takes to cover one mile at that speed. That makes it useful for drivers crossing between metric and imperial countries, boaters and pilots working in knots, physics students who need SI units, and runners translating a treadmill mph setting into a pace.
All the conversion factors are exact, so results are limited only by rounding. For race planning by distance and finish time, the running pace calculator is the better tool; to check whether your speedometer reads true after a tire change, use the speedometer error calculator.
The formula
km/h = mph × 1.609344 m/s = km/h ÷ 3.6 knots = km/h ÷ 1.852 pace (min per mile) = 60 ÷ mph
| Symbol | Meaning | Unit |
|---|---|---|
| mph | Statute miles per hour; 1 mile = 1,609.344 m | mi/h |
| km/h | Kilometers per hour | km/h |
| m/s | Meters per second, the SI unit of speed | m/s |
| knot | One nautical mile (1,852 m) per hour | kn |
| ft/s | Feet per second; 1 ft = 0.3048 m, so 1 ft/s = 0.6818 mph | ft/s |
The mile and foot follow from the 1959 international yard (0.9144 m); the nautical mile was fixed at exactly 1,852 m by international agreement and is recognized by NIST and the BIPM. Pace is the reciprocal of speed, so it is not linear: going from 6 to 7 mph cuts pace by about 1 min 26 s per mile, while going from 9 to 10 mph cuts it by only 40 s.
Worked examples
Highway speed limit abroad
A US driver in Europe sees a 100 km/h limit sign and wants it in mph.
Inputs
- Speed100
- FromKilometres per hour
Result
- Miles per hour62.1372
- Kilometres per hour100
- Metres per second27.7778
- Knots53.9958
- Pace per mile0:58
100 km/h is 62.14 mph. A quick mental shortcut is to multiply km/h by 0.6 and add a little: 100 × 0.6 = 60, plus about 2.
Boat cruising speed in knots
A powerboat's chartplotter shows 20 knots and a passenger asks how fast that is on land.
Inputs
- Speed20
- FromKnots
Result
- Miles per hour23.0156
- Kilometres per hour37.0399
- Metres per second10.2889
- Knots20
- Pace per mile2:36
20 knots is about 23.0 mph or 37.0 km/h. Because a knot is the larger unit, a speed in knots is about 13% lower in number than the same speed in mph.
Treadmill speed to running pace
A runner sets a treadmill to 7.5 mph and wants to know the pace per mile.
Inputs
- Speed7.5
- FromMiles per hour
Result
- Miles per hour7.5
- Kilometres per hour12.0701
- Metres per second3.3528
- Knots6.5173
- Pace per mile8:00
7.5 mph is an 8:00-per-mile pace, or 12.07 km/h. Treadmill belts are not always calibrated, so a GPS or track check is worth doing before a race.
Common speeds in every unit
Rounded reference points for checking a conversion at a glance.
| Speed | mph | km/h | m/s | knots |
|---|---|---|---|---|
| Brisk walk | 3 | 4.8 | 1.3 | 2.6 |
| Common urban limit (30 mph) | 30 | 48.3 | 13.4 | 26.1 |
| 130 km/h motorway limit (e.g. France) | 80.8 | 130 | 36.1 | 70.2 |
| 70 mph highway limit | 70 | 112.7 | 31.3 | 60.8 |
| Speed of sound, sea level, 15 °C | 761 | 1,225 | 340.3 | 661 |
Knots, Mach and other specialist units
- Knots are used at sea and in aviation because a nautical mile was originally one minute of latitude, which makes distances on charts easy to measure.
- Mach number is speed divided by the local speed of sound, which falls with temperature. Mach 1 is about 761 mph at sea level in standard conditions but roughly 660 mph at airliner cruising altitude.
- Feet per second shows up in ballistics, falling-object problems and US engineering. Multiply ft/s by 0.6818 for mph.
- Wind speeds in weather forecasts may be in mph, km/h, m/s or knots depending on the country; marine forecasts use knots almost everywhere.
Pace vs speed for runners and walkers
Runners think in minutes per mile or per kilometer, while treadmills and cycle computers show speed. The converter's pace output is 60 ÷ mph. For pace per kilometer, divide 60 by the km/h figure instead: 12 km/h is a 5:00/km pace. At 60 mph the pace reads 1:00 per mile, which is a handy check that the conversion is working. For whole-race planning, use the marathon pace calculator.
How to use the Speed Converter
- 1Enter the speed as a number. Use a decimal point for fractions (7.5, not 7½).
- 2Choose the unit it is in: miles per hour, kilometers per hour, meters per second, knots or feet per second.
- 3Read the equivalents in every other unit.
- 4For running or walking, read the pace per mile; for pace per km, divide 60 by the km/h result.
Frequently asked questions
How do I convert km/h to mph?
Divide km/h by 1.609344, or multiply by 0.6214. For example, 50 km/h is 31.1 mph and 120 km/h is 74.6 mph.
How fast is a knot in mph?
One knot is 1.1508 mph or exactly 1.852 km/h. So a 30-knot wind is about 34.5 mph.
How do I convert m/s to km/h?
Multiply by 3.6, because one hour has 3,600 seconds and one kilometer has 1,000 meters. 10 m/s is 36 km/h, or about 22.4 mph.
What pace per mile is 6 mph?
6 mph is a 10:00-per-mile pace, since 60 ÷ 6 = 10 minutes. 8 mph is 7:30 per mile and 10 mph is 6:00 per mile.
Why do planes use knots instead of mph?
Aviation and marine navigation share charts measured in nautical miles, so speed in knots lines up directly with chart distances. International aviation standards also specify knots for airspeed.
References
- NIST Special Publication 811, Guide for the Use of the International System of Units (SI) — National Institute of Standards and Technology
- The International System of Units (SI Brochure) — Bureau International des Poids et Mesures (BIPM)
About this calculator
- Built and reviewed by the Calculation Machine team · How we build and test calculators
- Last reviewed: October 24, 2026
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