Unit converter
Knots to Miles Per Hour Converter
Convert knots to miles per hour for boating, aviation weather, marine forecasts, and flight planning notes. The exact factor used by this calculator is 1.1507794480235427, meaning 1 knot is 1.1507794480235427 mph. A knot is based on one nautical mile per hour, and the unit table sets that speed at 0.5144444444444445 metres per second. Miles per hour use 0.44704 metres per second. This makes the page useful when a wind report, tide table, aircraft groundspeed, or yacht log needs a land-speed comparison.
1 knot = 1.1508 miles per hour
Common knots to miles per hour values
| Knots | Miles per hour |
|---|---|
| 1 kn | 1.1508 mph |
| 2 kn | 2.3016 mph |
| 5 kn | 5.7539 mph |
| 10 kn | 11.5078 mph |
| 20 kn | 23.0156 mph |
| 50 kn | 57.539 mph |
| 100 kn | 115.08 mph |
How to convert
- Take the speed measured in knots.
- Multiply it by 1.1507794480235427 to get the matching speed in miles per hour.
- The factor comes from 0.5144444444444445 divided by 0.44704, the two metres-per-second base values in the unit table.
- To convert mph back to knots, divide the mph value by 1.1507794480235427.
- For quick mental maths, add 15 percent to the knot value: 20 kn is close to 23 mph, and 40 kn is close to 46 mph.
mph = knots * 1.1507794480235427
The calculator converts both units through metres per second. A knot carries the base value 0.5144444444444445, while one mph is represented by 0.44704. Dividing the first by the second gives 1.1507794480235427, so each knot is a little more than one mile per hour.
- knots
- the marine or aviation speed you start with
- 1.1507794480235427
- miles per hour in one knot
Worked example
A coastal forecast listing 25 kn gusts is 25 multiplied by 1.1507794480235427, which is about 28.77 mph. A small craft seeing sustained 15 kn wind would be dealing with about 17.26 mph, before local gusts or shelter effects are considered.
Key facts
- 1 knot is 1.1507794480235427 mph.
- 20 knots is about 23.02 mph.
- A 30 knot wind is about 34.52 mph.
- Aircraft and vessel speeds often stay in knots because routes and charts use nautical miles.
Tips
- Add 15 percent for a fast estimate, then use the exact factor when logging or comparing figures.
- For weather briefings, keep wind speeds and gusts in the units used by the forecast source to avoid confusion.
- When comparing boat speeds with road speeds, remember that current can affect ground speed separately from speed through water.
Frequently asked questions
How many mph are in 1 knot?+
One knot is 1.1507794480235427 miles per hour using the exact factor calculated from the units in this project.
Why do sailors use knots rather than mph?+
Navigation at sea is tied to nautical miles, charts, bearings, and latitude. Knots keep speed in the same nautical frame instead of switching to statute miles.
Is a knot faster than one mph?+
Yes. Since 1 knot is 1.1507794480235427 mph, a speed in knots will be numerically smaller than the same speed written in mph.
How fast is 10 knots in normal road-speed terms?+
10 knots is about 11.51 mph. That is slow for a car but meaningful on water, where hull shape, current, and wind make small speed changes matter.
Things to watch
- Knots measure speed, not distance. A nautical mile is the distance unit behind the speed.
- Marine safety decisions should use the forecast unit as published, especially when local rules set thresholds in knots.
Sources
- NOAA note explaining knots and nautical miles · NOAA Ocean Service
- NIST reference for the international mile · NIST
Last updated: 2026-01-01
Conversions use internationally defined factors. Provided for general use; verify critical measurements independently.