Knots to miles per hour (kn to mph)

1 kn = 1.15077944802 mph. To convert knots to miles per hour, multiply by 1.15077944802.

The formula

mph = kn × 1.150779448

Where the factor comes from — each unit by its definition, then its size in SI:

  • 1 kn = nmi / h = 0.514444444444 m/s
  • 1 mph = mi / h = 0.44704 m/s

Dividing the two SI sizes gives the factor: 1.15077944802 (rounded for display; the underlying ratio is fixed by the definitions). The reverse factor is 0.868976241901.

Kinematics and energy formulas need speed in metres per second. Road speeds come in km/h or mph, so convert before you square anything: kinetic energy goes with v², so a unit slip is squared too.

Worked examples

  • Motorway driving (100 km/h): 53.9957 kn = 62.1371 mph — 53.9957 × 1.150779448 = 62.1371
  • A brisk walk (5 km/h): 2.69978 kn = 3.10686 mph — 2.69978 × 1.150779448 = 3.10686
  • US highway driving: 52.1386 kn = 60 mph — 52.1386 × 1.150779448 = 60
  • A hard-thrown ball (30 m/s): 58.3153 kn = 67.1081 mph — 58.3153 × 1.150779448 = 67.1081

Frequently asked questions

How many miles per hour is 1 kn?

1 kn = 1.15077944802 mph.

How do I convert miles per hour back to knots?

Divide by 1.15077944802 — or multiply by 0.868976241901: 1 mph = 0.868976241901 kn.

kn to mph conversion table

Knots (kn)Miles per hour (mph)
11.1507794
22.3015589
33.4523383
44.6031178
55.7538972
66.9046767
78.0554561
89.2062356
910.357015
1011.507794
1517.261692
2023.015589
2528.769486
3034.523383
4046.031178
5057.538972
6069.046767
7080.554561
7586.308459
8092.062356
90103.57015
100115.07794
150172.61692
200230.15589
250287.69486
500575.38972
1,0001,150.7794

Definitions: BIPM, The International System of Units (SI Brochure), 9th edition (2019), Tables 2, 4 and 8 — https://www.bipm.org/en/publications/si-brochure · International yard and pound agreement (1959): 1 yd = 0.9144 m, 1 lb = 0.45359237 kg; adopted in NIST SP 811 B.8 and NIST Handbook 44 Appendix C. Machine value of the factor: 1.15077944802.