Sound Distance Calculator (Thunder)

Estimate how far away a lightning strike is by timing the delay between the flash and the thunder.

Count seconds between the flash and the sound.
Speed of sound increases slightly with temperature.
We’ll show the distance in your chosen unit.
How we calculate

Speed of sound (dry air) is approximated as: v ≈ 331 + 0.6×T (m/s), where T is °C. Distance ≈ v × time.