Morse Code Converter

Text to ITU Morse and back, with signal units and send time.

Other ToolsUpdated 2026-10-112 min read
Morse Code Converter
Letters, digits, spaces and . , : ? ' - / ( ) " = + @ for encoding; dots, dashes, spaces, / for decoding.
Result
...
Signal units...
Send time...

What it does

Morse code turns letters into dots and dashes on a fixed clock. SOS becomes ... --- ... with single spaces between letters, and at 20 words a minute the 27 units take about 1.6 seconds to key. The tool above encodes and decodes to the ITU international standard with timing beside it.

Timing is the part most charts skip. Dots last 1 unit and dashes 3, with 1 unit inside letters, 3 between letters, and 7 between words. Counting SOS gives 5 plus 3 plus 11 plus 3 plus 5, which is 27 units, and each unit at 20 wpm is 0.06 seconds.

The standard behind the table is ITU-R M.1677, in force for international Morse across amateur and former maritime services. Its set holds 26 letters, 10 digits, and 12 punctuation marks including period, comma, question, slash, and the at sign added in 2004. Marks like exclamation and ampersand ride along unofficially and stay out of this converter.

Decoding runs the table backwards with slashes splitting words. Unknown groups stop the tool with an error instead of a guess, so check dot counts on long digits where five signal patterns blur together.

How to use

  1. Pick text to Morse or Morse to text.
  2. Type the message; encoding accepts letters, digits, spaces, and standard marks.
  3. For decoding, separate letters with spaces and words with /.
  4. Set keying speed in words per minute.
  5. Read the result first, timing beside it.

Formula

Dot 1, dash 3, intra gap 1, letter gap 3, word gap 7. Seconds = units x 1.2 / wpm.
unit
One dot length; 50 units make a PARIS word minute.
wpm
Words per minute keying speed.
/
Word separator in Morse text.

ITU M.1677-1 character set only. Prosigns, accents beyond E, and nonstandard marks are rejected rather than guessed.

Worked example

Example: SOS at 20 wpm

Defaults: encode, SOS, 20 wpm.

  1. Letters: S is ..., O is ---, S is ....
  2. Join: ... --- ... with single spaces.
  3. Units: 5 + 3 + 11 + 3 + 5 = 27.
  4. Seconds: 27 x 1.2 / 20 = 1.6 s.
  5. Tool shows ... --- ..., 27 units, 1.6 s at 20 wpm.

Reference table

Common codes with unit counts
CharCodeUnits
A.-5
B-...9
S...5
O---11
1.----17

Limits

  • ITU set only; ! ; & $ _ rejected.
  • No prosigns or accented letters.
  • Timing assumes perfect spacing.
  • Case ignored; all output is uppercase.

Common mistakes

  • Typing ! or & and expecting standard codes.
  • Merging letters without spaces.
  • Using line breaks instead of / between words.
  • Reading digit patterns as letters.
  • Ignoring speed when estimating air time.

Try it yourself

Quick checks. Answers sit tucked under each question.

Encode HI?

.... .., 13 units, 0.8 s at 20 wpm.

Decode ... --- ...?

SOS, 27 units, 1.6 s at 20 wpm.

Encode A?

.-, 5 units, 0.3 s at 20 wpm.

Questions

What is SOS in Morse?

... --- ... with spaces between letters.

How long is SOS at 20 wpm?

27 units, about 1.6 seconds.

Why is ! rejected?

It sits outside ITU M.1677; use a period instead.

How are words split?

Slash with spaces: ... / ... for two words.

Dots versus dashes?

Dash lasts 3 units to a dot 1 unit.

What standard is this?

ITU-R M.1677-1 international Morse.

Sources

How this page was checked. The formula above was matched against the cited sources, and the worked example was run through the tool on this page before publishing. If you spot an error, contact us so we can fix it and note the correction.