Kilometer per second (km/s)
Exactly 1000 meters per second.
What is a kilometer per second?
- Symbol
- km/s
- Quantity
- Speed
- Unit system
- SI
- Definition
- Exactly 1000 meters per second.
- Exact
- Yes, the value is exact by definition
- Source
- SI Brochure, 9th edition (BIPM, 2019)
Common applications
Used for the speeds of spacecraft, meteors and planets.
Kilometer per second in other speed units
- 1 km/s = 100000 cm/sCentimeter per second
- 1 km/s = 1000 m/sMeter per second
- 1 km/s = 3600 km/hKilometer per hour
- 1 km/s ≈ 2236.936292 mphMile per hour
- 1 km/s ≈ 3280.839895 ft/sFoot per second
- 1 km/s ≈ 1943.844492 knKnot
- 1 km/s ≈ 0.000003335640952 cSpeed of light in vacuum
Kilometer per second quick reference
| Kilometer per second | Kilometer per hour | Mile per hour | Centimeter per second |
|---|---|---|---|
| 1 km/s | = 3600 km/h | ≈ 2236.936292 mph | = 100000 cm/s |
| 10 km/s | = 36000 km/h | ≈ 22369.36292 mph | = 1000000 cm/s |
| 100 km/s | = 360000 km/h | ≈ 223693.6292 mph | = 10000000 cm/s |
| 1000 km/s | = 3600000 km/h | ≈ 2236936.292 mph | = 100000000 cm/s |
Where the kilometer per second fits
The next smaller speed unit is the meter per second (m/s). 1 km/s = 1000 m/s, and 1 m/s = 0.001 km/s.
The next larger speed unit is the speed of light (c). 1 km/s ≈ 0.000003335640952 c, and 1 c = 299792.458 km/s.
Frequently asked questions
- How many kilometers per hour are in one kilometer per second?
- One kilometer per second = 3600 km/h (kilometers per hour).
- How many miles per hour are in one kilometer per second?
- One kilometer per second ≈ 2236.936292 mph (miles per hour).
- How many centimeters per second are in one kilometer per second?
- One kilometer per second = 100000 cm/s (centimeters per second).