Morse Code to Text Decoder

A Morse code to text decoder is a translator that splits Morse code into letter groups and looks each group up in the Morse table. The group ··· becomes S, −−− becomes O, and ··· −−− ··· becomes SOS.

The decoder first detects the notation you pasted. Dots can arrive as periods, middle dots or bullets, dashes as hyphens, underscores or minus signs, and some sources write Morse as syllables or as ones and zeros.

The decoder reads Morse code in 4 steps: normalise, split words, split letters and look up. It converts every notation to plain dots and dashes, splits at slashes or wide gaps into words, splits at spaces into letters, and matches each letter group to a character.

Spacing decides the result. ·− · (with a space) reads AE, while ·−· (no space) reads R, so a missing space changes the letter.

Morse code spacing follows 3 rules: no gap inside a letter, 1 space between letters and a slash between words. In sound or light, these gaps last 1, 3 and 7 units, and written Morse represents them with nothing, a space and a slash.

If a message has no slashes, the decoder treats 3 or more spaces in a row as a word break, which matches how many radio logs are typed.

Morse code that won't decode usually has a missing space, an extra symbol or the wrong dash character. The decoder marks each unreadable group in red and lists the letters that are one symbol away from it.

Turn on auto-repair to replace each unreadable group with its closest letter. Check the result in context, because a one-symbol slip can match more than one letter.