Distance divided by time.
Kilometer per Seconds to Speed of lights Converter — km/s to c
Convert Kilometer per Seconds (km/s) to Speed of light (c) using the exact conversion factor (1 kilometer per seconds = 0.0000033356 speed of light). See the formula, worked examples, and conversion table.
Kilometer per Seconds to Speed of lights converter
Converter
Speed Converter
Convert road, aviation, marine, lab, and scientific speed units.
Context values
Some unit families need one extra value for a physically accurate result.
Speed of light in vacuum.
Result = input x 1000 / 2.99792458e+8.
Speed uses meters per second as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Kilometer per Seconds to Speed of lights
Kilometer per Seconds and Speed of light both describe speed, and the conversion matters whenever a maritime or aviation speed (knots) needs to be compared against a road speed (mph). Specifically: Distance divided by time, and speed of light in vacuum.
Formula
speed of lights = kilometer per seconds × 0.00000333564095198
This factor comes from each unit's defined relationship to the category's base unit: 1 kilometer per seconds equals 1000 base units, and 1 speed of light equals 299792458 base units, so dividing one by the other gives the direct kilometer per seconds-to-speed of light factor of 0.00000333564095198.
Simple example
1 km/s × 0.000003335640952 = 0.0000033356 c
1 kilometer per seconds = 0.0000033356 speed of lights.
Real-world example
10 km/s × 0.000003335640952 = 0.0000333564 c
10 kilometer per seconds = 0.0000333564 speed of lights.
Conversion table
| Kilometer per Seconds (km/s) | Speed of light (c) |
|---|---|
| 1 km/s | 0.0000033356 c |
| 5 km/s | 0.0000166782 c |
| 10 km/s | 0.0000333564 c |
| 25 km/s | 0.000083391 c |
| 50 km/s | 0.000166782 c |
| 100 km/s | 0.0003335641 c |
Reverse conversion: Speed of light to Kilometer per Seconds
0.0000033356 c × 299792.458 = 0.9999877229 km/s
0.0000033356 speed of lights = 0.9999877229 kilometer per seconds.
kilometer per seconds = speed of lights × 299792.458
For a page dedicated to this direction, see Speed of light to Kilometer per Seconds.
Understanding the Kilometer per Seconds (km/s)
Distance divided by time.
Understanding the Speed of light (c)
Speed of light in vacuum.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many speed of lights are in 1 kilometer per seconds?
1 kilometer per seconds equals 0.0000033356 speed of lights, using the exact defined conversion factor rather than an estimate.
How do I convert kilometer per seconds to speed of light?
Multiply the kilometer per seconds value by 0.000003335640952. The converter above does this instantly to whatever precision you set.
How do I convert speed of light back to kilometer per seconds?
Use the reverse factor: 1 speed of light equals 299,792.458 kilometer per seconds. You can also use the swap control in the converter above to flip the direction instantly.
What is a kilometer per seconds?
Kilometer per Seconds (km/s) is a unit of speed.
What is a speed of light?
Speed of light (c) is a unit of speed.
Is the kilometer per seconds to speed of light conversion exact?
Yes. Both kilometer per seconds and speed of light are defined by fixed standards rather than physical artifacts, so the factor of 0.000003335640952 used above is exact to as many digits as you choose to display.