/lightning — Lightning Distance
Light reaches you almost instantly; sound does not. Time the gap between the flash and the thunder and this works out how far away the strike was. Tap the buttons, or let your camera and microphone detect the flash and the clap automatically. Nothing is recorded or uploaded.
0.00 s
— km · — mi
Waiting for the flash…
Point the camera at the sky and keep the mic uncovered. Auto-detection is experimental: a bright window, passing headlights or a loud noise can trigger it. The manual buttons are always more reliable.
Rule of thumb: every 3 seconds ≈ 1 km, every 5 seconds ≈ 1 mile. If the flash and bang are simultaneous, the storm is right on top of you — seek shelter.