speed of light value
The speed of light in vacuum is exactly 299,792,458 m/s (c), or about 1,079,252,848.8 km/h.
Open the interactive OmniConvert tool →Key facts
| c (in m/s) | 299,792,458 m/s (exact) |
|---|---|
| c (in km/s) | 299,792.458 km/s |
| c (in km/h) | 1,079,252,848.8 km/h |
| 1 light-second | 299,792,458 m |
Frequently asked questions
What is the speed of light?
The speed of light in vacuum is exactly 299,792,458 metres per second, a defined constant since 1983.
How far does light travel in one second?
Light travels 299,792,458 metres (one light-second) per second in vacuum.
Related pages
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