# Knots to Mach Number Conversion

Enter the speed in knots below to get the value converted to Mach number.

**Results in Mach Number:**

## How to Convert Knots to Mach Number

To convert a knot measurement to a Mach measurement, multiply the speed by the conversion ratio. One knot is equal to Mach 0.0015, so use this simple formula to convert:

The Mach number is equal to the speed in knots multiplied by 0.0015.

**For example,**here's how to convert 5 knots to Mach number using the formula above.

Knots and Mach number are both units used to measure speed. Keep reading to learn more about each unit of measure.

## Knots

One knot is equal to a speed of one nautical mile per hour,^{[1]} or one minute of latitude per hour.

Knots can be abbreviated as *kn*, and are also sometimes abbreviated as *kt*. For example, 1 knot can be written as 1 kn or 1 kt.

## Mach Number

Mach, sometimes also referred to as a Mach number, is the ratio of the speed of an object to the speed of sound.^{[2]}

Mach can be abbreviated as M, and is also sometimes abbreviated as Ma. For example, Mach 1 can be written as 1 M or 1 Ma.

Although Mach can be abbreviated *M* or *Ma*, the Mach number is typically expressed with the number after the unit name.
For example, the expression *Mach 3* is preferred rather than *3 Machs* or *3 M*.

The speed is classified as either subsonic, transonic, supersonic, or hypersonic depending on the Mach number.

Speed Classification | Mach Number |
---|---|

Subsonic | Mach < 1.0 |

Transonic | Mach = 1.0 |

Supersonic | Mach > 1.0 |

Hypersonic | Mach > 5.0 |

## Knot to Mach Conversion Table

Knots | Mach Number |
---|---|

166.68 kn | Mach 0.25 |

333.37 kn | Mach 0.5 |

500.05 kn | Mach 0.75 |

666.74 kn | Mach 1 |

1,000 kn | Mach 1.5 |

1,333 kn | Mach 2 |

1,667 kn | Mach 2.5 |

2,000 kn | Mach 3 |

2,334 kn | Mach 3.5 |

2,667 kn | Mach 4 |

3,000 kn | Mach 4.5 |

3,334 kn | Mach 5 |

3,667 kn | Mach 5.5 |

4,000 kn | Mach 6 |

4,334 kn | Mach 6.5 |

4,667 kn | Mach 7 |

5,001 kn | Mach 7.5 |

5,334 kn | Mach 8 |

5,667 kn | Mach 8.5 |

6,001 kn | Mach 9 |

6,334 kn | Mach 9.5 |

6,667 kn | Mach 10 |

## References

- NASA, Knots Versus Miles per Hour, https://www.grc.nasa.gov/WWW/K-12/WindTunnel/Activities/knots_vs_mph.html
- NASA, Mach Number, https://www.grc.nasa.gov/WWW/BGH/mach.html