Emergency · Distress signal
SOS in Morse Code
SOS is ... --- ... — three dots, three dashes, three dots, sent as one continuous signal. It is loaded below so you can hear the rhythm or translate any other word.
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Farnsworth keeps each character at 18 WPM but slows the gaps to 18 WPM — ideal for learning. Set both equal for standard timing.
Timing follows ITU 1:3:7 · 100% client-side
Background
The universal distress signal
SOS became the international distress signal in 1905 and was written into global radio regulations in 1908. It was picked not for its letters but for itsunmistakable rhythm: dot-dot-dot dash-dash-dash dot-dot-dot, run together without the usual gaps between letters so it reads as a single, continuous call for help.
You can send it with anything that switches on and off — a flashlight, a mirror, a whistle or a radio key. Send three short, three long, three short, pause, then repeat. Because it is a genuine emergency signal, only use SOS when real help is needed.
How to signal
Light, sound and tapping
SOS is a rhythm, not a word, so you can send it through almost any channel. Keep short signals short, long signals about three times as long, and run the nine parts together with no letter gaps:
- Flashlight or phone torch. Three quick flashes, three long flashes, three quick flashes. Best at night or toward search aircraft and boats.
- Whistle or horn. Three short blasts, three long, three short. Sound carries when you cannot be seen — useful in fog, forest or surf.
- Tapping or knocking. Tap the pattern on a pipe, wall or hull if you are trapped. Metal carries the sound far through a building or vessel.
- Mirror or reflective surface. Flash sunlight in the SOS rhythm toward rescuers during the day.
Pause for a few seconds, then repeat. Press Play on the tool above to memorise the timing before you need it.
Answers
SOS FAQ
What is SOS in Morse code?
SOS is three dots, three dashes, three dots — ... --- ... — sent as one continuous signal with no letter gaps, which makes it instantly recognisable.
Does SOS stand for anything?
No. SOS was chosen in 1905 because its pattern is simple and unmistakable. Backronyms like 'Save Our Souls' came later and are not the origin.
How do I signal SOS with light or sound?
Send three short signals, three long signals, then three short again, pause, and repeat. Use a flashlight, whistle or any on/off source. Only signal SOS in a real emergency.