SOS in Morse Code
SOS in Morse code is ... --- ... — three dots, three dashes, three dots. Play it, learn why it was chosen, and send it by light, sound or tapping.
What does SOS mean?
Nothing — and that is the point. SOS is not an abbreviation of "Save Our Souls" or "Save Our Ships"; those backronyms came later. It was adopted in 1906 as a maritime distress call simply because the pattern is unmistakable: three dots, three dashes, three dots. There is no meaning to decode, no language to translate — just a rhythm anyone can key under pressure.
Why is SOS three dots, three dashes, three dots?
The sequence was chosen for its symmetry. It reads the same in both directions, its rhythm punches through static, and the nine elements are short enough to key quickly with cold hands on a wet key. It was also distinct from the older CQD call, so there could be no confusion about what was being sent.
How to send an SOS signal
Three ways, one rhythm. By sound: three short tones, three long tones, three short tones. By light: the same pattern with a flashlight or a headlamp. By tapping: on a pipe, a wall, a car hood. Keep the proportions — a dash lasts as long as three dots — and put a clear pause between the letters so the listener can split S from O.
SOS vs. Mayday and other distress signals
Mayday is the spoken distress call for voice radio; SOS is its Morse code counterpart. Pan-Pan signals urgency without immediate danger. SOS predates them all and remains the written and keyed form of the same message — which is why every radio operator, pilot and sailor still learns it first.
How to send SOS Morse code with a flashlight
By flashlight
Three quick blinks, pause, three long blinks, pause, three quick blinks. Repeat until answered.
By whistle or horn
Three short blasts, three long blasts, three short blasts. The rhythm carries over wind and engines.
By tapping
On a pipe, radiator or car hood — three taps, three slow drags, three taps. It works through walls.
Frequently asked questions
›Is SOS an abbreviation?
No. Contrary to a popular belief, SOS does not stand for "Save Our Souls" or "Save Our Ships" — it was chosen in 1906 simply because three dots, three dashes and three dots form an unmistakable, easy-to-key pattern that is hard to mistake for anything else.
›Why was ... --- ... chosen as the distress signal?
The sequence is symmetric and rhythmic: three short, three long, three short. It reads the same forwards and backwards, carries through noisy channels, and can be keyed quickly by anyone — even with no training at all.
›How do I send SOS with a flashlight?
Turn the torch on and off: three quick flashes for the dots, pause, three longer flashes for the dashes, pause, three quick flashes again. Roughly one second per dot and three seconds per dash keeps the rhythm readable.
›Is the SOS signal the same in every country?
Yes. Morse code is an international standard, and ... --- ... means distress everywhere — at sea, on land and in the air. There are no local variations of the SOS pattern.
›How fast should I play the SOS signal?
The player defaults to 20 WPM, where a dot lasts 60 milliseconds. For learning, drop to 5-10 WPM so each element is clearly separate; the loop toggle repeats the signal until you stop it.