A concise introduction to Morse code — a 180-year-old signalling system developed for the telegraph. Learn how dots and dashes represent letters and numbers, and why pilots, ham radio operators, and the military still rely on it today.
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Origin: how Morse code was born
In the 1830s, American painter-turned-inventor Samuel Morse and his colleague Alfred Vail developed the electric telegraph together with a code that could represent letters and numbers as short and long electrical pulses — dots and dashes. The first official message, "What hath God wrought", was sent from Washington, D.C. to Baltimore in 1844 and marked the birth of electronic long-distance communication.
How the code is structured
Each letter maps to a unique sequence of dots (·, short pulse) and dashes (–, long pulse). The most frequent letters get the shortest codes to save time: E = ·, T = –, A = ·–, N = –·. Letters, digits 0–9, and common punctuation are all covered. The modern standard is International Morse Code, formalised in 1865 and still in use today.
Timing rules make it readable
A dash is 3× the length of a dot. Gaps also carry meaning: 1 unit of silence separates signals within a letter, 3 units separate letters, and 7 units separate words. Without consistent timing a message quickly becomes ambiguous — which is why good operators practice rhythm before speed.
Where Morse code is still used
Aviation: VOR and NDB navigation beacons still broadcast their identifier in Morse. Amateur radio: CW (continuous wave) is the preferred mode for long-distance low-power contacts on shortwave. Maritime: SOS (··· ––– ···) remains an internationally recognised distress signal. Military: a low-bandwidth emergency fallback. Accessibility: patients with locked-in syndrome can communicate via eye blinks mapped to Morse.
Try our Morse Code Translator
Paste any text to encode it as Morse, or paste dots and dashes to decode back into text. The tool also plays audio so you can hear the rhythm — useful if you're learning or practising for an amateur radio exam. Everything runs in your browser, no sign-up required.
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Morse Code Translator
Questions fréquentes
Q: What does SOS stand for?
A: Nothing — it's not an acronym. The sequence ··· ––– ··· was adopted internationally in 1906 because the pattern is short, symmetric, and nearly impossible to confuse with anything else. "Save Our Souls" and "Save Our Ship" are popular backronyms invented later.
Q: Is Morse code still an official requirement anywhere?
A: Aviation still uses it for navigation beacon identifiers, and many countries require amateur radio operators to demonstrate Morse reception for higher-class licences — though the FCC in the US dropped that requirement in 2007. The International Maritime Organization retired mandatory Morse for merchant ships in 1999.
Q: How fast can people send Morse code?
A: Casual learners work at 5–10 words per minute. Experienced ham radio operators comfortably send 25–40 wpm. Competitive high-speed telegraphy contests see humans decoding above 60 wpm, and specially trained operators have exceeded 75 wpm.