Knots to Mach Number Converter

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

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1 kn = Mach 0.0015

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How to Convert Knots to Mach Number

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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:

Mach number = knots × 0.0015

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.
5 kn = (5 × 0.0015) = Mach 0.007499

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

What is a Knot?

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.

Learn more about knots.

What is 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 classifications for various mach numbers.
Speed Classification Mach Number
Subsonic Mach < 1.0
Transonic Mach = 1.0
Supersonic Mach > 1.0
Hypersonic Mach > 5.0

Learn more about Mach number.

Knot to Mach Conversion Table

Mach numbers converted to Mach number
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

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

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