Morse code to text: how to translate dots and dashes
To translate Morse code into text, split the message into words at each slash, split each word into letters at each single space, then look up each group of dots and dashes in a Morse chart. A dot is a dit, a dash is a dah, and the exact order of the two, not just how many there are, decides the letter. A short message takes a few minutes with a pencil. The only real work is in the groups that match nothing, and those almost always come from a missing or extra space.
Read the notation before you translate
Written Morse uses two symbols and two kinds of break:
| You see | It means |
|---|---|
. |
a dit, the short element |
- |
a dah, the long element |
| one space | the end of a letter |
/ |
the end of a word |
So .... .. is two letters, H and I, and .... .. / - .... . .-. . is HI THERE.
Not everyone writes it that way. You will meet middle dots or bullets for dits (· and •), underscores or long dashes for dahs, a vertical bar or a new line between words, and sometimes just a wider space. None of that changes the code. Before you look anything up, rewrite the message in plain periods and hyphens, with one space between letters and a slash between words. It takes a minute and removes most mistakes before they happen.
One warning: if you see a single long dash where the rhythm needs two dahs, distrust it. Some word processors and website editors turn two hyphens into one dash on their own, so that “one dah” may really have been two. How to copy and paste Morse code so it reads right explains how that happens and how to undo it. For the conventions themselves, see How to write Morse code in text.
Translating by hand, step by step
- Mark the words. Draw a line at every slash, so you work through one short chunk at a time.
- Count the elements in each group. Only six letters have one or two elements, so short groups go quickly.
- Look up each group. Use a chart, the table below, or the Morse tree, where (in the usual layout) you start at the top and go left for a dit and right for a dah until you run out of elements.
- Write each letter directly above its group, not on a separate line. When something does not fit later, you can see exactly which group produced it.
- Read the word back. If it makes sense, move on. If it does not, go to the next section before you guess.
Sorting the letters by length makes the lookup much faster, because a three-element group can only be one of eight letters:
| Elements | Letters |
|---|---|
| 1 | E . T - |
| 2 | I .. A .- N -. M -- |
| 3 | S ... U ..- R .-. W .-- D -.. K -.- G --. O --- |
| 4 | H .... V ...- F ..-. L .-.. P .--. J .--- B -... X -..- C -.-. Y -.-- Z --.. Q --.- |
The figures are all five elements long, which makes them easy to spot. From 1 to 5, the figure tells you how many dits come first, and dahs fill the rest: 1 is .----, 3 is ...--, 5 is ...... From 6 to 9 it flips, with dahs first: 6 is -...., 8 is ---.., and 0 is five dahs, -----. Most punctuation is six elements: the period is .-.-.-, the comma --..-- and the question mark ..--...
Here is a full example to try: -- . . - / .- - / -.... / .--. --. Split at the slashes and you get four words. The first is M, E, E, T. The second is A, T. The third is a single figure, 6. The last is P, M. The message is MEET AT 6 PM.
If you find the tree easier than a list, The Morse code tree shows how to read one.
When a group matches nothing
Sooner or later you will hit a group that is not in any chart. Four-element groups such as ..--, .-.-, ---. and ---- are not letters in the international alphabet (some languages use them for extra letters of their own), and apart from the dollar sign ...-..-, the error signal and SOS, nothing in the usual charts runs longer than six elements. When a group fails, work through these causes in order.
Two letters ran together. Someone left out a letter gap, either when writing it down or when copying it by ear. Try splitting the group into two real letters and keep the split that makes a word. Six dits, ......, is not a character, but it can split as .... .. (HI), ... ... (SS) or ..... . (5E). Context decides, and in a greeting it is almost certainly HI.
One letter was split in two. An extra space inside a letter turns L, .-.., into .- .., which reads as A and I. This one is harder to catch because both halves are real letters; you only notice when the word is nonsense. Try joining neighboring groups and see whether a better word appears.
It is a prosign. Prosigns are letters sent as one character on purpose, so they look like a run-together group. At the end of a message, .-.-. is AR, end of message (it is also the plus sign). -...- is BT, a break between parts of a message (also the equals sign). ...-.- is SK, end of contact. And ...---... is SOS, sent as one nine-element character. Morse code prosigns explained covers the rest.
It is the error signal. A run of eight dits, ........, means the sender made a mistake. Usually the sender then sends the last word again, so cross out the word before it and read what follows as the correction.
You genuinely cannot tell. Write a question mark in its place and read on. One unknown letter in a word is usually obvious from the rest, the same way you can read a word with one smudged letter.
Translating Morse on a Mac
A pencil is fine for a line or two. For a long message, or when you want to check your hand translation, a translator saves time. On a Mac, Dot & Dash has one in Transcribe: choose Morse to Text, type or paste the dots and dashes, and the message appears as you go. It reads periods and hyphens with spaces between letters and / between words, and it also takes a middle dot or bullet for a dit, an underscore or en dash for a dah, and |, three or more spaces or a new line between words. Any other character is ignored. From there you can Play the message on the machine, Copy Text, Copy Morse or Save it to the Library. It reads typed or pasted Morse only; it does not listen to sound.
Checking a translation
Whichever way you translate, give the result one last read with these in mind:
- Read it aloud. A wrong letter in the middle of a word often only shows up when you hear the word.
- Look at the letters most often swapped. A and N are mirror images (
.-and-.), and so are D and U (-..and..-), G and W (--.and.--), B and V (-...and...-). One misread element in a long letter also makes a real but wrong letter: P (.--.) and J (.---) differ only in the last element. - Expect radio shorthand. A message copied from amateur radio is full of abbreviations that look like errors but are not: CQ for calling any station, DE for “from”, K for “over”, TU for thank you, 73 for best regards, and signal reports like 599.
- Respect the figures. A five-element group in the middle of letters is usually a figure. If it reads as nonsense, recount its dits and dahs before you change anything else.
Questions
Is a dot the same as a dit?
Yes. In written Morse the short element is a dot and the long one a dash; spoken or heard, they are called a dit and a dah. A dah lasts three times as long as a dit.
What does a slash mean in written Morse code?
A slash with a space each side marks the gap between two words. The slash character also has its own Morse code, -..-., so if that pattern appears inside a message, it is a slash in the text.
Why does my translation have wrong letters in it?
Usually because of spacing, not the code. A missing space merges two letters into one, and an extra space splits one letter into two, so check the groups around any odd letter first.
Can I translate Morse code without knowing it?
Yes. With a chart and the steps above, anyone can translate written Morse; it is slower than recognizing the patterns, but just as accurate if you check each group.