# Mach Number Conversion Calculator

Enter a value in Mach number below to convert to another unit of speed.

## Results:

## What Is Mach Number?

Mach number is a unit used to measure speed.

Mach, sometimes also referred to as a Mach number, is the ratio of the speed of an object to the speed of sound.^{[1]}

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 |

### Background and Origin

The Mach number is named for Austrian physicist Ernst Mach to recognize his work in the study of sound waves.

## How Fast is Mach Speed?

When an object is moving faster than the speed of sound, it is moving at Mach speed. Since Mach numbers describe the ratio between an object's speed to the speed of sound, an object moving at Mach 1 is moving at the speed of sound, and an object moving at Mach 2 is moving at two times the speed of sound.

The chart below shows how fast Mach speed is in miles per hour.

Mach Number | Miles per Hour |
---|---|

Mach 1 | 767.269148 mph |

Mach 2 | 1,535 mph |

Mach 3 | 2,302 mph |

Mach 4 | 3,069 mph |

Mach 5 | 3,836 mph |

Mach 6 | 4,604 mph |

Mach 7 | 5,371 mph |

Mach 8 | 6,138 mph |

Mach 9 | 6,905 mph |

Mach 10 | 7,673 mph |

## How to Convert Mach Number

To convert Mach number to another unit of speed, you need to multiply the value by a conversion factor.
A conversion factor is a numerical value used to change the units of a measurement without changing the value.^{[2]}

You can find the conversion factors for Mach number in the conversion table below.

Then, multiply the speed measurement by the conversion factor to find the equivalent value in the desired unit of measurement.

Mach number × conversion factor = result

You can also use a calculator, such as one of the converters below, for the conversion.

## Mach Conversion Table

Mach number | knots | speed of sound | speed of light | miles per hour | feet per second | kilometers per second | kilometers per hour | meters per second | centimeters per second |
---|---|---|---|---|---|---|---|---|---|

Mach 1 | 666.738661 kn | 1 sound | 0.0000011441 c | 767.269148 mph | 1,125 ft/s | 0.343 km/s | 1,235 km/h | 343 m/s | 34,300 cm/s |

Mach 2 | 1,333 kn | 2 sound | 0.0000022882 c | 1,535 mph | 2,251 ft/s | 0.686 km/s | 2,470 km/h | 686 m/s | 68,600 cm/s |

Mach 3 | 2,000 kn | 3 sound | 0.0000034324 c | 2,302 mph | 3,376 ft/s | 1.029 km/s | 3,704 km/h | 1,029 m/s | 102,900 cm/s |

Mach 4 | 2,667 kn | 4 sound | 0.0000045765 c | 3,069 mph | 4,501 ft/s | 1.372 km/s | 4,939 km/h | 1,372 m/s | 137,200 cm/s |

Mach 5 | 3,334 kn | 5 sound | 0.0000057206 c | 3,836 mph | 5,627 ft/s | 1.715 km/s | 6,174 km/h | 1,715 m/s | 171,500 cm/s |

Mach 6 | 4,000 kn | 6 sound | 0.0000068647 c | 4,604 mph | 6,752 ft/s | 2.058 km/s | 7,409 km/h | 2,058 m/s | 205,800 cm/s |

Mach 7 | 4,667 kn | 7 sound | 0.0000080089 c | 5,371 mph | 7,877 ft/s | 2.401 km/s | 8,644 km/h | 2,401 m/s | 240,100 cm/s |

Mach 8 | 5,334 kn | 8 sound | 0.000009153 c | 6,138 mph | 9,003 ft/s | 2.744 km/s | 9,878 km/h | 2,744 m/s | 274,400 cm/s |

Mach 9 | 6,001 kn | 9 sound | 0.000010297 c | 6,905 mph | 10,128 ft/s | 3.087 km/s | 11,113 km/h | 3,087 m/s | 308,700 cm/s |

Mach 10 | 6,667 kn | 10 sound | 0.000011441 c | 7,673 mph | 11,253 ft/s | 3.43 km/s | 12,348 km/h | 3,430 m/s | 343,000 cm/s |

Mach 11 | 7,334 kn | 11 sound | 0.000012585 c | 8,440 mph | 12,379 ft/s | 3.773 km/s | 13,583 km/h | 3,773 m/s | 377,300 cm/s |

Mach 12 | 8,001 kn | 12 sound | 0.000013729 c | 9,207 mph | 13,504 ft/s | 4.116 km/s | 14,818 km/h | 4,116 m/s | 411,600 cm/s |

Mach 13 | 8,668 kn | 13 sound | 0.000014874 c | 9,974 mph | 14,629 ft/s | 4.459 km/s | 16,052 km/h | 4,459 m/s | 445,900 cm/s |

Mach 14 | 9,334 kn | 14 sound | 0.000016018 c | 10,742 mph | 15,755 ft/s | 4.802 km/s | 17,287 km/h | 4,802 m/s | 480,200 cm/s |

Mach 15 | 10,001 kn | 15 sound | 0.000017162 c | 11,509 mph | 16,880 ft/s | 5.145 km/s | 18,522 km/h | 5,145 m/s | 514,500 cm/s |

Mach 16 | 10,668 kn | 16 sound | 0.000018306 c | 12,276 mph | 18,005 ft/s | 5.488 km/s | 19,757 km/h | 5,488 m/s | 548,800 cm/s |

Mach 17 | 11,335 kn | 17 sound | 0.00001945 c | 13,044 mph | 19,131 ft/s | 5.831 km/s | 20,992 km/h | 5,831 m/s | 583,100 cm/s |

Mach 18 | 12,001 kn | 18 sound | 0.000020594 c | 13,811 mph | 20,256 ft/s | 6.174 km/s | 22,226 km/h | 6,174 m/s | 617,400 cm/s |

Mach 19 | 12,668 kn | 19 sound | 0.000021738 c | 14,578 mph | 21,381 ft/s | 6.517 km/s | 23,461 km/h | 6,517 m/s | 651,700 cm/s |

Mach 20 | 13,335 kn | 20 sound | 0.000022882 c | 15,345 mph | 22,507 ft/s | 6.86 km/s | 24,696 km/h | 6,860 m/s | 686,000 cm/s |

## Mach Conversion Calculators

You can also convert speed using one of our Mach converters below.

- Mach number to knots converter
- Mach number to speed of sound converter
- Mach number to speed of light converter
- Mach number to miles per hour converter
- Mach number to feet per second converter
- Mach number to kilometers per second converter
- Mach number to kilometers per hour converter
- Mach number to meters per second converter
- Mach number to centimeters per second converter

## References

- NASA, Mach Number, https://www.grc.nasa.gov/WWW/BGH/mach.html
- National Institute of Standards & Technology, Unit Conversion, https://www.nist.gov/pml/owm/metric-si/unit-conversion