Feet Per Second to Mach Number Conversion

Enter the speed in feet per second below to get the value converted to Mach number.

Results in Mach Number:
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1 ft/s = Mach 0.000889

How to Convert Feet Per Second to Mach Number

To convert a foot per second measurement to a Mach measurement, multiply the speed by the conversion ratio. One foot per second is equal to Mach 0.000889, so use this simple formula to convert:

Mach number = feet per second × 0.000889

The Mach number is equal to the speed in feet per second multiplied by 0.000889.

For example, here's how to convert 5 feet per second to Mach number using the formula above.
5 ft/s = (5 × 0.000889) = Mach 0.004443

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

Feet Per Second

Feet per second are a measurement of speed expressing the distance traveled in feet in one second.

The foot per second is a US customary and imperial unit of speed. Feet per second can be abbreviated as ft/s, and are also sometimes abbreviated as ft/sec or fps. For example, 1 foot per second can be written as 1 ft/s, 1 ft/sec, or 1 fps.

In formal expressions, the slash, or solidus (/), is used to separate units used to indicate division in an expression.[1]

Feet per second can be expressed using the formula:
vft/s = dft / tsec

The velocity in feet per second is equal to the distance in feet divided by time in seconds.

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

Foot Per Second to Mach Conversion Table

Mach numbers converted to Mach number
Feet Per Second Mach Number
281.33 ft/s Mach 0.25
562.66 ft/s Mach 0.5
844 ft/s Mach 0.75
1,125 ft/s Mach 1
1,688 ft/s Mach 1.5
2,251 ft/s Mach 2
2,813 ft/s Mach 2.5
3,376 ft/s Mach 3
3,939 ft/s Mach 3.5
4,501 ft/s Mach 4
5,064 ft/s Mach 4.5
5,627 ft/s Mach 5
6,189 ft/s Mach 5.5
6,752 ft/s Mach 6
7,315 ft/s Mach 6.5
7,877 ft/s Mach 7
8,440 ft/s Mach 7.5
9,003 ft/s Mach 8
9,565 ft/s Mach 8.5
10,128 ft/s Mach 9
10,691 ft/s Mach 9.5
11,253 ft/s Mach 10


  1. National Institute of Standards and Technology, NIST Guide to the SI, Chapter 6: Rules and Style Conventions for Printing and Using Units, https://www.nist.gov/pml/special-publication-811/nist-guide-si-chapter-6-rules-and-style-conventions-printing-and-using
  2. NASA, Mach Number, https://www.grc.nasa.gov/WWW/BGH/mach.html

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