Lightning Distance Calculator
Approximate how far lightning struck by multiplying the seconds until thunder by the speed of sound in air (0.343 km/s).
For safety awareness only; seek shelter during storms regardless of distance.
Examples
- 3 s ⇒ 1.03 km
- 5 s ⇒ 1.72 km
FAQ
Why use 0.343 km/s?
It's the approximate speed of sound in air at sea level.
Does wind affect the result?
Wind and temperature can slightly change sound speed.
Can I get distance in miles?
Multiply seconds by 0.213 to convert to miles.
Is this exact?
It's an estimate; terrain and atmospheric conditions may alter sound travel.
Additional Information
- Sound travels about 343 meters per second at 20°C in dry air.
- Multiply seconds by 0.213 to estimate distance in miles or by 343 for meters.
- Temperature, humidity, and altitude can slightly change the speed of sound.