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Morse code: letters, digits and signals

Learn International Morse code: all 26 letters, the 10 digits, common punctuation and signals like SOS, each with its rhythm and a memory aid.

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A

Letter

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  1. 1
    A
    Letter
    · −
    Said “di-dah”. The reverse of N
  2. 2
    B
    Letter
    − · · ·
    Said “dah-di-di-dit”. The reverse of V
  3. 3
    C
    Letter
    − · − ·
    Said “dah-di-dah-dit”. Sounds like N twice
  4. 4
    D
    Letter
    − · ·
    Said “dah-di-dit”. The reverse of U
  5. 5
    E
    Letter
    ·
    Said “dit”. A single dit: the shortest code, for the most common letter in English
  6. 6
    F
    Letter
    · · − ·
    Said “di-di-dah-dit”. The reverse of L
  7. 7
    G
    Letter
    − − ·
    Said “dah-dah-dit”. The reverse of W
  8. 8
    H
    Letter
    · · · ·
    Said “di-di-di-dit”. Four dits. E, I, S and H each add one more
  9. 9
    I
    Letter
    · ·
    Said “di-dit”. Two dits. Swap dits for dahs and you get M
  10. 10
    J
    Letter
    · − − −
    Said “di-dah-dah-dah”. A dit followed by O
  11. 11
    K
    Letter
    − · −
    Said “dah-di-dah”. R with dits and dahs swapped. On its own it means “over to you”
  12. 12
    L
    Letter
    · − · ·
    Said “di-dah-di-dit”. The reverse of F
  13. 13
    M
    Letter
    − −
    Said “dah-dah”. Two dahs. T, M and O each add one more
  14. 14
    N
    Letter
    − ·
    Said “dah-dit”. The reverse of A
  15. 15
    O
    Letter
    − − −
    Said “dah-dah-dah”. Three dahs, the middle of SOS
  16. 16
    P
    Letter
    · − − ·
    Said “di-dah-dah-dit”. Reads the same both ways. Swap dits and dahs and you get X
  17. 17
    Q
    Letter
    − − · −
    Said “dah-dah-di-dah”. The reverse of Y
  18. 18
    R
    Letter
    · − ·
    Said “di-dah-dit”. Reads the same both ways. Swap dits and dahs and you get K
  19. 19
    S
    Letter
    · · ·
    Said “di-di-dit”. Three dits, the start and end of SOS
  20. 20
    T
    Letter
    −
    Said “dah”. A single dah, for the second most common letter in English
  21. 21
    U
    Letter
    · · −
    Said “di-di-dah”. The reverse of D
  22. 22
    V
    Letter
    · · · −
    Said “di-di-di-dah”. The reverse of B. Its rhythm matches the opening of Beethoven’s Fifth Symphony
  23. 23
    W
    Letter
    · − −
    Said “di-dah-dah”. The reverse of G
  24. 24
    X
    Letter
    − · · −
    Said “dah-di-di-dah”. Reads the same both ways. Also used as the multiplication sign
  25. 25
    Y
    Letter
    − · − −
    Said “dah-di-dah-dah”. The reverse of Q
  26. 26
    Z
    Letter
    − − · ·
    Said “dah-dah-di-dit”. Two dahs, then two dits
  27. 27
    1
    Digit
    · − − − −
    Said “di-dah-dah-dah-dah”. Digits 1 to 5 start with as many dits as the digit, then dahs to make five
  28. 28
    2
    Digit
    · · − − −
    Said “di-di-dah-dah-dah”. Two dits, then dahs to make five
  29. 29
    3
    Digit
    · · · − −
    Said “di-di-di-dah-dah”. Three dits, then dahs to make five
  30. 30
    4
    Digit
    · · · · −
    Said “di-di-di-di-dah”. Four dits, then a dah
  31. 31
    5
    Digit
    · · · · ·
    Said “di-di-di-di-dit”. All dits. Every digit is five elements long
  32. 32
    6
    Digit
    − · · · ·
    Said “dah-di-di-di-dit”. Digits 6 to 9 start with dahs, one for 6 up to four for 9, then dits to make five
  33. 33
    7
    Digit
    − − · · ·
    Said “dah-dah-di-di-dit”. Two dahs, then dits to make five
  34. 34
    8
    Digit
    − − − · ·
    Said “dah-dah-dah-di-dit”. Three dahs, then dits to make five
  35. 35
    9
    Digit
    − − − − ·
    Said “dah-dah-dah-dah-dit”. Four dahs, then a dit
  36. 36
    0
    Digit
    − − − − −
    Said “dah-dah-dah-dah-dah”. All dahs: the opposite of 5
  37. 37
    .
    Full stop (period)
    · − · − · −
    Said “di-dah-di-dah-di-dah”. A three times
  38. 38
    ,
    Comma
    − − · · − −
    Said “dah-dah-di-di-dah-dah”. Two dahs, two dits, two dahs
  39. 39
    ?
    Question mark
    · · − − · ·
    Said “di-di-dah-dah-di-dit”. The comma with dits and dahs swapped. Also used to ask for a repeat
  40. 40
    /
    Slash
    − · · − ·
    Said “dah-di-di-dah-dit”. X followed by a dit
  41. 41
    @
    At sign
    · − − · − ·
    Said “di-dah-dah-di-dah-dit”. A and C run together. Added to the international standard in 2004
  42. 42
    -
    Hyphen
    − · · · · −
    Said “dah-di-di-di-di-dah”. 6 followed by a dah
  43. 43
    '
    Apostrophe
    · − − − − ·
    Said “di-dah-dah-dah-dah-dit”. 1 followed by a dit
  44. 44
    (
    Opening bracket
    − · − − ·
    Said “dah-di-dah-dah-dit”. Y followed by a dit
  45. 45
    )
    Closing bracket
    − · − − · −
    Said “dah-di-dah-dah-di-dah”. Sounds like K twice
  46. 46
    SOS
    Signal: distress
    · · · − − − · · ·
    Said “di-di-di-dah-dah-dah-di-di-dit”. Sent as one unbroken signal, not as three letters. It doesn’t stand for anything
  47. 47
    AR
    Signal: end of message
    · − · − ·
    Said “di-dah-di-dah-dit”. A and R run together. The same code as +
  48. 48
    SK
    Signal: end of contact
    · · · − · −
    Said “di-di-di-dah-di-dah”. S and K run together, the last signal of a conversation
  49. 49
    BT
    Signal: break
    − · · · −
    Said “dah-di-di-di-dah”. B and T run together, to separate parts of a message. The same code as =
  50. 50
    HH
    Signal: error
    · · · · · · · ·
    Said “di-di-di-di-di-di-di-dit”. Eight dits, like H twice. The operator then resends the last word

Frequently asked questions

Should I learn Morse code by sight or by sound?

By sound, if you want to receive it. Operators learn each character as a rhythm, di-dah for A, rather than counting dots and dashes. Saying the rhythm aloud as you review helps.

How long are the dits, dahs and gaps?

A dah lasts as long as three dits. The gap inside a character is one dit long, between characters three dits, and between words seven dits.

What does SOS stand for?

Nothing. It was chosen because its pattern, three dits, three dahs and three dits, is easy to send and hard to mistake. It’s sent as one unbroken signal, not as three separate letters.

What are signals like AR and SK?

Two letters sent as one character, with no gap, to manage a conversation. AR ends a message, SK ends the contact, BT separates parts of a message, and eight dits mark an error.

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