Feet per second to miles per hour
Type a value in feet per second to see it in miles per hour straight away, or type in the second box to convert back.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Type the value in the feet per second box.
- Read the result in miles per hour as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
mph = ft/s × 0.6818181818
Multiply the value in feet per second by 0.6818181818 to get miles per hour.
Example
To convert 25 ft/s to miles per hour: 25 × 0.6818181818 = 17.0455 mph.
Conversion table
| Feet per second (ft/s) | Miles per hour (mph) |
|---|---|
| 1 | 0.681818 |
| 2 | 1.36364 |
| 3 | 2.04545 |
| 5 | 3.40909 |
| 10 | 6.81818 |
| 20 | 13.6364 |
| 25 | 17.0455 |
| 50 | 34.0909 |
| 100 | 68.1818 |
| 250 | 170.455 |
| 500 | 340.909 |
| 1,000 | 681.818 |
About the units
- Foot per second
- Covering one international foot (0.3048 m) in one second, exactly 0.3048 m/s. It appears in ballistics and US engineering.
- Mile per hour
- Covering one international mile (1609.344 m) in one hour, exactly 0.44704 m/s. It is used on roads in the United States and the United Kingdom.
Limits and caveats
- Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
- Both unit factors are exact by their official definitions.
Questions about this tool
How many miles per hour are in one foot per second?
1 ft/s = 0.681818 mph exactly.
How do I convert feet per second to miles per hour?
Use mph = ft/s × 0.6818181818. For example, 25 ft/s = 17.0455 mph.
How many feet per second are in one mile per hour?
1 mph = 1.46667 ft/s.
How do I convert km/h to m/s in my head?
Divide by 3.6, because an hour is 3600 seconds and a kilometer is 1000 meters. For example 72 km/h is 20 m/s; multiply by 3.6 to go back.
Why do Mach values differ between sources?
The speed of sound depends on air temperature. We use 340.294 m/s at sea level and 15 °C; at 11 km altitude it is about 295 m/s, so Mach 1 is slower there.