How To Convert Feet per Second to Kilometers per Hour
Formula: km/h = ft/s × 1.09728
Example: Convert 18 ft/s to km/h.
18 × 1.09728 = 19.75104 km/h
To convert manually, take your speed in feet per second.
Multiply it by 1.09728 to get kilometers per hour.
This works because 1 foot is exactly 0.3048 meters, and 1 hour is 3600 seconds.
Quick Answer
1 ft/s = 1.09728 km/h
- 5 ft/s = 5.4864 km/h
- 10 ft/s = 10.9728 km/h
- 25 ft/s = 27.432 km/h
Conversion Formula
km/h = ft/s × 1.09728
This means you are changing a speed measured per second into a speed measured per hour, and also switching from feet to kilometers.
The number 1.09728 is built from exact definitions:
- 1 foot = 0.3048 meters (exact)
- 1 m/s = 3.6 km/h (exact, because 1 hour = 3600 seconds)
- So 1 ft/s = 0.3048 × 3.6 = 1.09728 km/h
Steps you can follow:
- Write your value in ft/s.
- Multiply by 1.09728.
- Keep the unit as km/h.
- Round only if you need fewer decimal places.
Foot per second
A foot per second is a unit of speed that tells how many feet an object moves in one second. Symbol: ft/s (or ft·s⁻¹).
It comes from the foot as a length unit used in the US customary and imperial systems, and the second from standard timekeeping. It is common in older engineering notes, sports timing, and US based measurements.
- Measuring short distance motion in labs
- Sports speeds for running drills
- Airflow and fan velocity in HVAC work
- Conveyor belt speeds in factories
- Simple physics problems in school
Kilometer per hour
A kilometer per hour is a unit of speed that tells how many kilometers an object moves in one hour. Symbol: km/h (or kph).
It grew with the metric system and became the standard road speed unit in most countries. It is widely used for driving speeds, weather reports, and travel planning.
- Road speed limits and car dashboards
- Cycling and running pace displays
- Weather wind speed reports in many regions
- Train and public transport schedules
- Fitness apps and GPS tracking
Is this Conversion of Feet per Second To Kilometers per Hour Accurate?
Yes. This conversion is based on exact, fixed definitions used in science and engineering. The foot is defined as exactly 0.3048 meters, and time conversion uses the exact relationship 1 hour = 3600 seconds. Combining these gives the exact factor 1 ft/s = 1.09728 km/h, so the results are reliable for homework, engineering estimates, and everyday use.
For more details on how we choose and verify standard constants, see our accuracy standards page.
Real Life Examples
Feet per second is common in US style measurements, while km/h is common in travel and road speeds. Here are realistic conversions you might actually use.
- Walking speed: A relaxed walk might be about 4 ft/s. 4 × 1.09728 = 4.38912 km/h.
- Fast walking: A brisk walk could be 6 ft/s. 6 × 1.09728 = 6.58368 km/h.
- Easy jogging: A light jog may be near 10 ft/s. 10 × 1.09728 = 10.9728 km/h.
- Short sprint: A quick sprint drill could hit 25 ft/s. 25 × 1.09728 = 27.432 km/h.
- Bike cruising: If a cycling sensor reports 30 ft/s, that is 30 × 1.09728 = 32.9184 km/h.
- Small drone or RC car: If it moves at 40 ft/s, then 40 × 1.09728 = 43.8912 km/h.
- Car speed in a simulation: If a model shows 60 ft/s, then 60 × 1.09728 = 65.8368 km/h.
Quick Tips
- Use the fixed multiplier: × 1.09728.
- For a fast estimate, multiply by about 1.1, then adjust slightly down.
- If you need more precision, keep 1.09728 until the final step, then round once.
- Check your unit labels, ft/s is per second, km/h is per hour.
- Reasonableness check, km/h should be a bit bigger than ft/s because 1.09728 is greater than 1.