Knots to MPH Converter
Convert knots to miles per hour and back. 1 knot = 1.15077944802 miles per hour (rounded).
Tip: Results show up to 8 significant digits. The factors and their sources are listed on the "Where our numbers come from" page.
On this page
Knots and MPH
One knot is about 1.15077944802 miles per hour, and one mile per hour is about 0.868976241901 knots. The converter works both ways: use the two tabs at the top of the tool to choose the direction.
Quick conversion table
Knots to MPH
| Knots | MPH |
|---|---|
| 1 kn | 1.1507794 mph |
| 2 kn | 2.3015589 mph |
| 5 kn | 5.7538972 mph |
| 10 kn | 11.507794 mph |
| 15 kn | 17.261692 mph |
| 20 kn | 23.015589 mph |
| 25 kn | 28.769486 mph |
| 30 kn | 34.523383 mph |
| 40 kn | 46.031178 mph |
| 50 kn | 57.538972 mph |
| 100 kn | 115.07794 mph |
MPH to Knots
| MPH | Knots |
|---|---|
| 1 mph | 0.86897624 kn |
| 5 mph | 4.3448812 kn |
| 10 mph | 8.6897624 kn |
| 20 mph | 17.379525 kn |
| 30 mph | 26.069287 kn |
| 40 mph | 34.75905 kn |
| 50 mph | 43.448812 kn |
| 60 mph | 52.138575 kn |
| 70 mph | 60.828337 kn |
| 100 mph | 86.897624 kn |
Exact factor and source
| Conversion | Value | Basis |
|---|---|---|
| 1 knot in miles per hour | 1.15077944802 | rounded to 12 digits. 1 knot = 1 nautical mile per hour; the international nautical mile is exactly 1852 m (NIST SP 811, App. B.8) |
| 1 mile per hour in knots | 0.868976241901 | rounded to 12 digits. NIST SP 811 (2008), Appendix B.8: 1 mi/h = 1609.344 m / 3600 s = 0.44704 m/s exactly |
How to convert knots to miles per hour
- Step oneTake the number of knots.
- Step twoMultiply it by 1.15077944802.
- Step threeThe result is the number of miles per hour.
- Step fourTo go back, divide by 1.15077944802, or multiply by 0.868976241901.
Example: 20 kn x 1.15077944802 = 23.0155889605 mph.
All speed units compared
Each unit written in meters per second, the base unit of this tool. Exact values come straight from the definitions.
| Unit | Symbol | Value in meters per second |
|---|---|---|
| Meters per second | m/s | 1 meter per second |
| Kilometers per hour | km/h | 0.277777777778 meters per second |
| Miles per hour | mph | 0.44704 meters per second |
| Knots | kn | 0.514444444444 meters per second |
What is a knot?
A knot (kn) is one nautical mile per hour. A nautical mile is exactly 1,852 meters, so one knot is 1.852 km/h, or about 1.15077944802 mph. Ships and aircraft use knots.
What is a mile per hour?
Miles per hour (mph) is the speed unit on road signs in the United States and the UK. One mph is exactly 1.609344 kilometers per hour, or 0.44704 meters per second.
What this converter does not do
- Results are rounded for display to 8 significant digits; the stored factor is the exact one.
- It converts a speed; it does not convert a speed into a pace such as minutes per mile.
- It does not know the speed limits of any road.
Frequently asked questions
How many miles per hour are in a knot?
1 knot is about 1.15077944802 miles per hour. The factor is rounded to 12 significant digits.
How many knots are in a mile per hour?
1 mile per hour is about 0.868976241901 knots.
How fast is 20 knots in miles per hour?
20 knots is 23.015589 mph, or 37.04 km/h.
Where do the factors come from?
Knots: 1 knot = 1 nautical mile per hour; the international nautical mile is exactly 1852 m (NIST SP 811, App. B.8). Miles per hour: NIST SP 811 (2008), Appendix B.8: 1 mi/h = 1609.344 m / 3600 s = 0.44704 m/s exactly.
References
- Knots: 1 knot = 1 nautical mile per hour; the international nautical mile is exactly 1852 m (NIST SP 811, App. B.8)
- MPH: NIST SP 811 (2008), Appendix B.8: 1 mi/h = 1609.344 m / 3600 s = 0.44704 m/s exactly
- NIST Special Publication 811: Guide for the Use of the International System of Units (SI), 2008 edition.
- The International System of Units (SI Brochure), 9th edition, BIPM.