Morse code · distress signalSOS in Morse Code
Three dots, three dashes, three dots — in one run, with no gaps between the letters. Listen to the signal, turn on a full-screen beacon and find out where “Save Our Souls” really came from.
Text ↔ Morse
SOS in one run, as a single signalSignal and beacon
These nine elements have 192 readings in Latin letters if you don't know where the letters end. That is why SOS is one signal, not three letters.
The beacon flashes. Do not use it if you are sensitive to flashing light.
How to signal SOS without a phone
With light
A torch, or a mirror in the sun: a short flash and one three times longer.
With sound
A whistle: three short, three long, three short.
By knocking
On a pipe or a wall, a long knock is a double one.
Signs on the ground
Large letters SOS of stones, branches or footprints in snow, visible from above.
History
- 1905Germany introduces the signal
- 1906The Berlin Radiotelegraph Convention adopts SOS internationally
- 1908The rule comes into force
- 1909First uses of SOS by ships in distress
- 1912Titanic's operators send both the old CQD and the new SOS
- 1999From 1 February SOS at sea gives way to the satellite-based GMDSS
About the signal
SOS is a single distress signal of nine elements. It was chosen not for its meaning but for its rhythm: easy to send, easy to hear and impossible to mistake for ordinary text. “Save Our Souls” and “Save Our Ship” are backronyms invented later to make the signal easier to remember.
One run
RuleSOS is sent with no gaps between the letters, as one block. Otherwise it is just three letters, S, O and S.
Not an acronym
MythThe signal was adopted in 1906 for its rhythm. “Save Our Souls” is a reading invented after the fact.
Before it, CQD
HistoryBefore SOS, Marconi company operators called for help with CQD. The new signal was simpler and more recognisable and gradually pushed the old one out.
With light
No radioA short flash is a dot, three times longer is a dash. A torch, a phone screen or a mirror in the sun will do.
Rule of three
No codeAny signal repeated three times is understood as a call for help — even by someone who doesn't know Morse.
GMDSS
TodayAt sea SOS was officially replaced by the satellite-based GMDSS. But the signal is still understood everywhere.
Frequently asked questions
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