text: how many times faster is the speed of light than the speed of sound?   the speed of light in a vacuum is 299,792,458 m/s exactly.  the speed of sound will varry depending on the medium and temperature at which it is propigating, but at sea level it is about 340 m/s when propigating through air.  so light would be about 8.82 e5 times faster than sound.