Velocity
ft/stomm/s
Convert feet per second (ft/s) to millimetres per second (mm/s).
Factor1 ft/s = 304.8 mm/s
Converter
ft/s
Accepts numbers or expressions, e.g. 150 + 14.7
Result
mm/s
Rendered to 6 significant figures.
Formula
Formula
mm/s = ft/s × 304.8
Multiply any value in feet per second by 304.8 to obtain the value in millimetres per second.
Worked example
Convert 1 ft/s to mm/s.
- 01Start with 1 ft/s.
- 02Multiply by the conversion factor: 1 × 304.8 = 304.8 mm/s.
Result1 ft/s = 304.8 mm/s
Conversion table
| ft/s | mm/s |
|---|---|
| 1 | 304.8 |
| 2 | 609.6 |
| 5 | 1524 |
| 10 | 3048 |
| 20 | 6096 |
| 50 | 15240 |
| 100 | 30480 |
| 200 | 60960 |
| 500 | 1.5240e+5 |
| 1000 | 3.0480e+5 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from ft/s to mm/s?
1 ft/s equals 304.8 mm/s. To convert, multiply the value in feet per second by 304.8.
How do I convert 1 ft/s to mm/s?
1 ft/s = 304.8 mm/s. For any value, multiply by 304.8.
How do I convert mm/s back to ft/s?
Divide by the same factor — or equivalently, multiply by 0.00328084. So 1 mm/s = 0.00328084 ft/s.
When would I need to convert foot per second to millimetre per second?
Velocity conversions are needed for fluid flow analysis (line velocity targets, erosional limits), gas-stream calculations, and equipment specs that mix m/s, ft/s and engineering speed units.
Is the conversion exact?
The factor shown is precise to at least 7 significant figures. For most process-engineering work this is far better than instrument accuracy. For metrology or trade applications, refer to the relevant national standard (NIST, BIPM, ISO 80000).