SOS in Morse code
SOS is the international distress signal: three dots, three dashes, three dots. In a real emergency it is sent as one continuous signal, without the usual pause between the letters, so it is really a single nine-part pattern rather than the word S O S. Operators write it with a bar over the top, or as <SOS>.
Where SOS comes from
SOS was adopted at the International Radiotelegraph Convention in Berlin in 1906 and came into force in 1908. It was chosen because the rhythm is easy to send and impossible to mistake, even through static. It does not stand for anything. "Save our souls" and "save our ship" were invented later to explain it.
Before SOS, British ships used CQD. When the Titanic sank in 1912, its radio operators sent both CQD and SOS, which helped make SOS known to the public. Ships stopped relying on Morse code for distress calls in 1999, when the satellite-based GMDSS system took over, but the pattern is still understood all over the world.
How to signal SOS without a radio
- With a flashlight: three short flashes, three long flashes, three short flashes, then a pause, and repeat. Press Flash above to do this with your phone screen.
- With a whistle or horn: three short blasts, three long, three short.
- By knocking: three quick knocks, three slow ones, three quick ones.
- On the ground: write SOS in large letters with stones, logs or in the snow, so it can be seen from the air.
In mountain areas the international distress signal is six signals a minute (whistle, light or shout), then a minute of silence. If you have a phone with reception, call the emergency number first.
Translate anything
Type any word into the Morse code translator to hear it, flash it or download it as audio. Every letter, number and sign is on the Morse code alphabet chart, and the trainer teaches you to read Morse code by ear.