Feet Per Second to Miles Per Hour
Type a value in either box to convert between feet per second and miles per hour. The factor is 0.681818.
| Feet Per Second | Miles Per Hour |
|---|---|
| 1 ft/s | 0.681818 mph |
| 2 ft/s | 1.363636 mph |
| 3 ft/s | 2.045455 mph |
| 5 ft/s | 3.409091 mph |
| 10 ft/s | 6.818182 mph |
| 25 ft/s | 17.045455 mph |
| 50 ft/s | 34.090909 mph |
| 100 ft/s | 68.181818 mph |
How to use
- Enter a value in the Feet Per Second field.
- The Miles Per Hour figure appears immediately — no button to press.
- Typing in the Miles Per Hour field converts back to Feet Per Second the same way.
- Use the reference table for the values that come up most often.
Feet Per Second to Miles Per Hour formula
Converting feet per second to miles per hour is a single multiplication by 0.681818182.
mph = ft/s × 0.681818182
Put another way, one foot per second is exactly 15/22 miles per hour.
Why this factor: the foot per second and the mile per hour are both defined against the meter per second, so dividing one definition by the other gives 0.681818182 directly. Both definitions are set out in full below.
To go the other way, divide by 0.681818182 — or use the Miles Per Hour to Feet Per Second converter, which is the same calculation reversed.
Worked example
Take 100 ft/s and multiply by the factor 0.681818182: the result is 68.181818 mph.
100 ft/s × 0.681818182 = 68.181818 mph
The converter above does this for any value you type, in either direction.
What is a foot per second?
Feet per second is a US engineering speed unit, common where distances are short.
Definition: Exactly 0.3048 meter per second, following from the exact definition of the foot.
Where it is used: Ballistics and muzzle velocities, fluid flow in pipes, and conveyor speeds in the US.
What is a mile per hour?
Miles per hour is the road speed unit of the United States and the United Kingdom.
Definition: Exactly 0.44704 meters per second, following from the exact 1,609.344 m mile.
Where it is used: US and UK speed limits and speedometers, plus baseball pitch and tennis serve speeds.
Feet Per Second vs Miles Per Hour
The foot per second and the mile per hour belong to the same family of units, so converting between them is usually a matter of shifting a decimal point or applying a small whole-number factor.
Frequently asked questions
How many miles per hour are in a foot per second?
One foot per second equals 0.681818182 miles per hour.
What is the formula to convert feet per second to miles per hour?
Multiply the number of feet per second by 0.681818182. To reverse it, divide by 0.681818182 instead.
How do I convert miles per hour back to feet per second?
Divide by 0.681818182, which is the same as multiplying by 1.46666667.
How many miles per hour are in 10 feet per second?
10 ft/s works out to 6.818182 mph.
How is the foot per second defined?
Exactly 0.3048 meter per second, following from the exact definition of the foot.