SOS in Morse code is ...---...: three dots, three dashes, three dots. It is sent as one continuous signal, with no pauses between the letters.
How SOS is sent
Written as three letters, SOS would be S ..., O ---, S ... with a gap after each letter. As a distress signal it is sent differently: the nine signals run together without letter gaps. That makes it a prosign, a single symbol rather than a word, and it is unmistakable even through noise.
You can hear the difference in the translator. Typing SOS plays three separate letters. Typing <SOS> plays the unbroken distress signal.
Open “<SOS>” in the translator
How to signal SOS without a radio
The same rhythm works with anything that can be short or long. Keep a dash about three times as long as a dot, and leave a clear pause before repeating.
- Light: short and long flashes with a torch, phone light or mirror. At night a flashlight can be seen from far away.
- Sound: short and long blasts on a whistle or horn. Three short, three long, three short.
- Tapping: knocks on a pipe, wall or door. Quick taps for dots, and a slower, heavier pattern or a scrape for dashes.
- On the ground: if you are lost outdoors, large letters "SOS" made from rocks, logs or trampled snow can be seen from the air.
In a real emergency, call your local emergency number first if you can. Morse code is a backup when other communication fails.
Does SOS stand for "Save Our Souls"?
No. SOS does not stand for anything. It was chosen because the pattern is simple, symmetrical and hard to mistake for anything else. "Save our souls" and "save our ship" are phrases people invented later to remember it.
A short history
Germany introduced SOS as its distress signal in 1905. The first International Radiotelegraph Convention, signed in Berlin on 3 November 1906, adopted it worldwide, and it came into force on 1 July 1908. Before that, ships using Marconi equipment sent CQD.
When the Titanic sank in April 1912, its radio operators sent both CQD and SOS. After that disaster, SOS became the call everyone used.
SOS stayed the official maritime distress signal in Morse code until 1999, when the satellite-based Global Maritime Distress and Safety System (GMDSS) replaced Morse code at sea. Pilots and ships now use "Mayday" for voice distress calls.
Sources: SOS on Wikipedia, ITU-R M.1677-1.
Other emergency signals
| Signal | Morse code | Meaning |
|---|---|---|
| SOS | ...---... | Distress: immediate help needed |
| CQD | -.-. --.- -.. | Old distress call, replaced by SOS |
| HELP | .... . .-.. .--. | Plain word; works but is longer |
| Mayday | spoken | Voice distress call on radio |