Conversion tool
Convert feet per second to kilometers per hour instantly
Enter a value, see the result, copy it, and save a PDF snapshot.
Input
Type a value, then press Enter to calculate.
Result
0.000 km/h
Rounded for readability. Use the arrows to increase or decrease the number of shown digits.
Estimation mode
Enter your estimate in km/h, then reveal to compare.
Reveal summary
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- Percent error
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Disclaimer: Use calculations at your own risk. For critical applications, verify results against your governing standards/specifications.
How it works
We use km/h = ft/s x 1.09728.
Exact relationship: 1 ft/s = 1.09728 km/h.
Example: 1 ft/s = 1.097 km/h.
Notes: Results are rounded in the default view.
Examples
- 1 ft/s = 1.097 km/h
- 30 ft/s = 32.918 km/h
- 100 ft/s = 109.728 km/h
FAQ
What physical quantity do feet per second and kilometers per hour express?
Feet per second are a customary speed unit used to describe rate of motion, flow, and travel in U.S.-oriented technical contexts. Kilometers per hour are a metric speed unit used to describe travel rate, vehicle speed, and route progress.
What is the difference between feet per second and kilometers per hour?
Feet per second and kilometers per hour both express speed, but they come from different measurement conventions and are used in different technical and transportation contexts.
What is the history of the foot per second?
Feet per second developed from customary distance and time measures and remain useful where feet are already the working length unit.
What is the history of the kilometer per hour?
Kilometers per hour emerged naturally from metric distance and time usage as transportation systems standardized around the metric system.
Were the foot per second and kilometer per hour discovered by a specific person?
Feet per second evolved as a practical derived unit rather than being discovered by one person. Kilometers per hour came from unit-system standardization, not from a single discoverer.
Where are feet per second and kilometers per hour used in science and engineering?
Feet per second appear in ballistics, motion systems, fluid references, ventilation work, and machine-rate calculations. Kilometers per hour are common in international road systems, transportation planning, testing, and global product documentation.
Why do speed units matter in calculations?
Speed units affect motion planning, travel estimates, machine timing, flow assumptions, and safety margins. Keeping the unit attached to the value helps prevent calculation mistakes.
Can I trust this for critical calculations?
Use this for convenience and verify against your governing standard, requirement, or control document for critical work. The arithmetic is straightforward, but system context still matters.
References
- Exact constant used: 1 ft/s = 1.09728 km/h.
- Speed conversions are derived from consistent distance-per-time relationships.