About

Morse code remains the only digital encoding scheme that a human can decode without equipment. Errors in transcription - a missing dot, a misplaced space - collapse the entire message because Morse is a variable-length prefix code: the symbol for E (a single dot) is a strict prefix of I (two dots). This tool implements the full ITU-R M.1677-1 character set and enforces correct spacing: 1 unit between elements, 3 units between characters, 7 units between words. Audio playback uses a 700 Hz sine tone at configurable words-per-minute. The timing formula is t_dot = 1200 ÷ WPM ms, calibrated against the word "PARIS" (50 units). Unsupported characters are silently dropped and flagged so you can correct your input before transmission.

Formulas

Morse code timing is derived from the Paris standard. The word "PARIS" encodes to exactly 50 dot-units, so one word-per-minute equals 50 units per 60 seconds.

t_dot = 1200WPM ms

t_dash = 3 × t_dot

t_intra-char = 1 × t_dot

t_inter-char = 3 × t_dot

t_word-gap = 7 × t_dot

Where t_dot is the base time unit, WPM is the transmission speed in words per minute. At 20 WPM, t_dot = 60 ms. Audio frequency is fixed at 700 Hz, the ITU recommended tone for radiotelegraphy practice.

Reference Data

Character	Morse Code	Character	Morse Code	Character	Morse Code
A	· −	N	− ·	0	− − − − −
B	− · · ·	O	− − −	1	· − − − −
C	− · − ·	P	· − − ·	2	· · − − −
D	− · ·	Q	− − · −	3	· · · − −
E	·	R	· − ·	4	· · · · −
F	· · − ·	S	· · ·	5	· · · · ·
G	− − ·	T	−	6	− · · · ·
H	· · · ·	U	· · −	7	− − · · ·
I	· ·	V	· · · −	8	− − − · ·
J	· − − −	W	· − −	9	− − − − ·
K	− · −	X	− · · −	,	− − · · − −
L	· − · ·	Y	− · − −	.	· − · − · −
M	− −	Z	− − · ·	?	· · − − · ·
!	− · − · − −	'	· − − − − ·	/	− · · − ·
(	− · − − ·	)	− · − − · −	&	· − · · ·
:	− − − · · ·	;	− · − · − ·	=	− · · · −
+	· − · − ·	-	− · · · · −	_	· · − − · −
"	· − · · − ·	$	· · · − · · −	@	· − − · − ·

Frequently Asked Questions

Variable-length encoding optimizes transmission speed. The most frequent letters in English - E (·) and T (−) - use a single element, while rare letters like Q (− − · −) use four. This is analogous to Huffman coding: average message length is shorter than any fixed-width scheme would produce for natural language text.

Unsupported characters (such as emoji, accented letters outside the basic set, or control characters) are dropped from the output and a notification lists the skipped characters. The converter processes the remaining valid characters without interruption. If you need extended Latin characters (e.g., Ä, Ñ), note that ITU extensions exist but are not universally recognized.

Within a single character, dots and dashes have no separator (they are printed adjacently). Between characters, a single space is used (representing 3 dot-units of silence). Between words, a forward slash surrounded by spaces ( / ) is used (representing 7 dot-units). This notation is the de facto standard for written Morse and allows lossless round-trip conversion.

Yes. Switch the direction toggle to "Morse → Text" mode. Enter Morse using dots (. or ·) and dashes (- or −), separate characters with spaces, and separate words with " / ". The decoder normalizes unicode dot/dash variants before lookup, so both keyboard-typed and copy-pasted Morse will parse correctly.

The 700 Hz tone sits in the peak sensitivity range of human hearing and is the standard CW (continuous wave) sidetone frequency recommended by ITU for radiotelegraphy. It provides good audibility without fatigue over extended listening sessions. The tool's speed control (5 - 40 WPM) adjusts element timing while keeping frequency constant.

The tool uses the Paris standard: the word "PARIS" equals exactly 50 dot-units. Therefore t_dot = 1200 ÷ WPM ms. At 20 WPM, each dot is 60 ms. This matches the calibration method used by ARRL and military training standards. Farnsworth spacing (extended inter-character gaps for learners) is not implemented.