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How to send Morse code

The full alphabet, numbers, key words and how to signal by light, sound or tapping — no battery needed.

📡 Communication & signalling
21 How-to · illustrated guide
Start here — the basics
  • Learn one idea: a short signal is a dot, a long one is a dash
  • Memorise SOS first: three short, three long, three short
  • Leave gaps — short between symbols, longer between letters and words
  • You can signal by light, by sound or by tapping

Morse code turns any on/off signal — a torch, a whistle, a tapped pipe, a car horn — into letters. It needs no battery, no phone and no shared language, which is exactly why it still matters when everything else fails. You only have to learn one idea: short and long.

The two building blocks

  • A dot (·) is a short signal — call it "dit".
  • A dash (—) is a long signal, about three times as long — call it "dah".
  • Leave a short gap between dots and dashes, a letter-length gap between letters, and a word-length gap between words.
The one to memorise first: SOS. Three short, three long, three short — · · · — — — · · · — sent as one unbroken group. It is the international distress call and needs no spacing between the letters.

The full alphabet

LetterCode
A·—
B—···
C—·—·
D—··
E·
F··—·
G——·
H····
I··
J·———
K—·—
L·—··
M——
N—·
O———
P·——·
Q——·—
R·—·
S···
T—
U··—
V···—
W·——
X—··—
Y—·——
Z——··

Numbers

NumberCode
1·————
2··———
3···——
4····—
5·····
6—····
7——···
8———··
9————·
0—————

A few words worth knowing by heart

  • SOS — · · · — — — · · · — distress, send help.
  • OK — — — — / — · — — all is well.
  • YES — · — —— / · / · · ·    NO — — · / — — —.
  • HELP — · · · · / · / · — · · / · — — ·.
  • WATER, FOOD, HURT — practise these; in a real emergency they say almost everything.

How to send it

  • By light: a quick flash for a dot, a held flash for a dash. At night a torch carries a long way.
  • By sound: a whistle blast — short and long. Sound beats shouting and saves your voice.
  • By tapping: on a pipe, wall or hull — rescuers listen for exactly this.
Tip. Sending slowly and clearly is far better than fast and ragged. A steady rhythm is what makes Morse readable.

What to do and what to avoid

Do
  • Start with SOS and the few words you would most need
  • Send slowly and keep a steady rhythm
  • Use a whistle or torch — they carry much further than your voice
  • Practise until the common letters are automatic
Avoid
  • Don't rush — ragged timing is unreadable
  • Don't run symbols together without gaps
  • Don't rely on shouting when a whistle carries further
  • Don't break up SOS — it is sent as one unbroken group
Further information
International Morse reference ↗

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