Miles per hour to Knots Converter
Convert Miles per hour (mph) to Knots (kn) instantly, or use the conversion table below to look up common values.
Miles per hour to Knots conversion table
| Miles per hour (mph) | Knots (kn) |
|---|---|
| 1 | 0.868976 |
| 2 | 1.737952 |
| 3 | 2.606929 |
| 4 | 3.475905 |
| 5 | 4.344881 |
| 10 | 8.689762 |
| 25 | 21.724406 |
| 50 | 43.448812 |
| 100 | 86.897624 |
How to convert Miles per hour to Knots
1 mph equals 0.868976 kn. Use the converter above for any value, or read the table for common conversions.
kn = mph × 0.8689762419006478 · mph = kn × 1.1507794480235427Multiply a miles per hour figure by 0.868976 to get knots, or divide it by 1.150779 to go the other way.
Worked examples
- 1 mph= 0.868976 kn
- 5 mph= 4.344881 kn
- 10 mph= 8.689762 kn
- 30 mph= 26.069287 kn
- 50 mph= 43.448812 kn
What these units are
Miles per hour (mph). A mile per hour is 0.44704 meters per second. It is the road-speed unit in the United States and the United Kingdom, and appears on imported vehicle speedometers.
Knots (kn). A knot is one nautical mile per hour, or 0.514444 meters per second. It is the standard unit for the speed of ships and aircraft.
The 3.6 factor between m/s and km/h is exact, so those two convert losslessly. Knots and miles per hour are exact definitions as well.
Converting Miles per hour to Knots in practice
Working in miles per hour
A mile per hour is one statute mile, exactly 1,609.344 meters, travelled in one hour. Miles per hour and kilometers per hour relate by exactly 1.609344, and one mile per hour is exactly 0.44704 meters per second.
It is used on road signs and in vehicle speed limits, in motoring and tyre specifications, in wind and weather reports, and in aviation and motorsport figures.
One mile per hour is exactly 1.609344 km/h, and that metric relationship needs no rounding. A knot is not a mile per hour, since one uses the nautical mile of 1,852 meters and the other the statute mile.
Treating a mile per hour as a knot is the usual mistake, because both count distance over an hour. A vessel or aircraft figure in knots needs the nautical mile before it can be compared with road speed.
The siblings are kilometers per hour, knots and meters per second. Posted road speeds in miles per hour belong to this unit, metric road and wind figures belong to kilometers per hour, navigation belongs to knots, and scientific measurement belongs to meters per second.
Reading the result in knots
A knot is exactly one nautical mile per hour, and a nautical mile is exactly 1,852 meters. One knot therefore equals exactly 1.852 kilometers per hour, a ratio that needs no rounding.
The unit belongs to marine and air navigation, where it gives vessel and aircraft speeds, wind reports at sea, and current and tidal stream rates.
A knot converts to exactly 1.852 km/h, so its metric relationships are exact. It uses the nautical mile of 1,852 meters while a mile per hour uses the statute mile, so the two must not be treated as the same unit.
The common mistake is treating a knot as a mile per hour and reusing a road speed figure at sea. The nautical and statute miles differ, so the error grows with the distance covered.
Two units sit closest to the knot: miles per hour and kilometers per hour. Navigation at sea and in the air is worked in knots, road speeds in miles per hour use that unit, and metric road and weather figures use kilometers per hour.
Checking a miles per hour to knots conversion
Every speed unit is a distance over a time, so the conversion factor is just the distance factor divided by the time factor. Meters per second to kilometers per hour is a single multiplication by exactly 3.6, and a reader can hold that number.
The candidates for confusion are the mile and the nautical mile, because both appear in speed units. A knot is one nautical mile per hour, and a nautical mile is 1,852 meters against the statute mile's 1,609.344, so a knot is about 15% faster than a mile per hour. Treating the two as interchangeable understates a marine or aviation speed.
To check a speed conversion, convert it to meters per second and compare with something known, such as walking pace. The error to avoid is applying the 3.6 factor to a pair that is not m/s to km/h, when the correct move is to convert the distance and the time separately.
Tanzania reference points
Real quantities, converted into the units on this page.
The speed limit in built-up areas in Tanzania
50 km/h = 31.06856 mph = 26.99784 kn
Source: Road Traffic Act [Cap.168 R.E 2002] s.51, summarised by FB Attorneys · verified 2026-09-14
The maximum speed outside built-up areas for vehicles over 3,500 kg in Tanzania
80 km/h = 49.709695 mph = 43.196544 kn
Outside built-up areas the limit for other vehicles is set by posted signs and road markings rather than a single national figure.
Source: Road Traffic Act [Cap.168 R.E 2002] s.51, summarised by FB Attorneys · verified 2026-09-14
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