What does morse code sound like?
Like a single steady tone switched on and off. Every sound is either a dit, one unit long, or a dah, three units long, and nothing else. The silences carry as much as the tones do: one unit inside a character, three between characters and seven between words.
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The flashlight needs camera access. Nothing is recorded or sent.
The word Hello at 10 words per minute. Change the speed and the rhythm stays the same while the clock speeds up.
One tone, two lengths
There is only one sound in morse and it never changes pitch. A key switches a steady tone on and off, and the message is in how long it stays on and how long it stays off.
ITU-R M.1677-1 allows two lengths of sound. A dit is one unit. A dah is three. At 20 words per minute (WPM) a unit is 60 milliseconds, so a dit is a 60 millisecond beep and a dah a 180 millisecond one. Drop to 5 WPM and the same two sounds become 240 and 720 milliseconds, but their relationship does not move.
Most of it is silence
New listeners hear the beeps and miss the gaps, which is where half the information is. The standard sets three of them:
- one unit between the marks inside a character
- three units between characters
- seven units between words
Play the word above and count them. The four dits of H run together, then a three-unit gap, then the single dit of E, and so on. Take the character gaps away and the same marks regroup into different letters.
Why the rhythm is learned, not read
A chart is useful for looking a character up and close to useless for reading morse at speed, because nobody can count four beeps and match them to a row in the time it takes to send the next letter. The ARRL’s advice is to learn each character by the way it sounds, as dits and dahs, rather than as dots and dashes on a page.
That is also why the speeds on our player start at 5 WPM rather than at something slower. Stretching the characters themselves teaches a rhythm that has to be unlearned later; the usual fix is to send the characters at full speed and stretch only the gaps between them.
Hearing it at real speeds
The ARRL publishes recordings of its W1AW code practice runs at speeds from 5 to 40 WPM, which is a fair range for what morse actually sounds like on the air. To hear your own text instead, type it into the morse code translator and press Play, or start with the nine marks of the distress signal on the SOS page.
Questions people ask next
What does a dit sound like?
A short beep of one unit, which is 60 milliseconds at 20 words per minute. A dah is the same tone held three times as long.
Does the pitch of morse code matter?
No. The message is in the lengths of the tones and the silences, so two operators sending at different pitches send the same code.
How fast is morse code sent?
Commonly between 5 and 40 words per minute. The ARRL's W1AW code practice recordings cover that whole range.
What does SOS sound like?
Three short tones, three long ones and three short ones, run together with no pause between the letters. You can play it on our SOS page.
Why does morse code sound like one note?
Because the transmitter sends a single steady tone and the key only switches it on and off. That kind of signal is called a continuous wave, or CW.
Related answers
- Is morse code hard to learn?
The characters are easy; hearing them at speed is the slow part.
- Does morse code have spaces?
Yes, three of them, and they carry as much as the marks do.
- Why is morse code called CW?
CW stands for continuous wave, which is the kind of radio signal that carries it.
Sources
- Codes and timing follow Recommendation ITU-R M.1677-1 (10/2009), International Morse code (International Telecommunication Union, 2009).
- Learning morse code (American Radio Relay League).