Convert knots to miles per hour in one step. Type a value, change the units if you need a different pair, and the answer updates as you type, with the reverse rate and a quick reference list.
Results are estimates for planning. Check the figures before you make a financial or health decision.
How to convert knots to miles per hour
Multiply the number of kn by 1.150779 to get mph:
mph = kn × 1.150779
To go the other way, divide by 1.150779 (or multiply by 0.868976). The converter stores each unit as a multiple of a base unit, so you can also pick any other pair of units from the same group.
Worked example
Using the default values in the converter above:
| Input | Value |
|---|---|
| Value | 20 |
| From | Knots |
| To | Miles per hour |
20 knots equals 23.015589 miles per hour
Knots to MPH reference table
| Knots | Miles per hour |
|---|---|
| 5 kn | 5.753897 mph |
| 10 kn | 11.507794 mph |
| 20 kn | 23.015589 mph |
| 30 kn | 34.523383 mph |
| 40 kn | 46.031178 mph |
| 50 kn | 57.538972 mph |
| 60 kn | 69.046767 mph |
| 70 kn | 80.554561 mph |
| 100 kn | 115.077945 mph |
Tips and common mistakes
UK road signs and speed limits use miles per hour, while most of Europe uses kilometres per hour. A mile is 1.609344 km, so 70 mph is about 112.7 km/h and 100 km/h is about 62.1 mph.
A knot is one nautical mile per hour, and a nautical mile is exactly 1,852 metres, so 1 knot is 1.852 km/h or about 1.151 mph. Knots are used at sea and in aviation, including wind speeds on marine forecasts.
The usual mistake is using the 1.6 shortcut and then forgetting which way it goes: multiply by about 1.6 to go from mph to km/h, and divide by about 1.6 (or multiply by 0.62) to go back.
Frequently asked questions
How many miles per hour are in 1 kn?
1 kn equals 1.150779 miles per hour.
How do I convert kn to mph by hand?
Multiply the kn figure by 1.150779. For example, 20 kn × 1.150779 = 23.015589 mph.
How do I convert mph back to kn?
Divide the mph figure by 1.150779, or multiply it by 0.868976. For example, 23.015589 mph is 20 kn.
Is this conversion exact?
Yes. The mile, nautical mile and knot are defined exactly in metric terms, so the factor is exact apart from rounding.