Morse Code Audio and Timing

Morse code is really a rhythm. Get the timing right and a message is clear; get it wrong and even correct dots and dashes become unreadable. Here's how the timing works and what the common speed terms mean.

Everything is measured in dot units

The whole system is built on one base length: the duration of a single dot, called a unit. Everything else is a multiple of it.

So the letter C (-.-.) is: dash (3), gap (1), dot (1), gap (1), dash (3), gap (1), dot (1) — a specific, repeatable rhythm. Change the ratios and it stops sounding like C.

What "words per minute" means

Speed in Morse is measured in words per minute (WPM), and by convention the reference word is PARIS — because its dots, dashes, and gaps add up to exactly 50 units, a good average for English. At 1 WPM you'd send PARIS once a minute; at 20 WPM, twenty times.

A simple formula falls out of this: the length of one dot in milliseconds is 1200 ÷ WPM. At 20 WPM, a dot is 60 ms. The audio player in the translator uses exactly this relationship, so moving the speed slider changes the real timing — not just the playback rate of a recording.

Farnsworth timing: the learner's trick

There's a problem when you're starting out. If you slow everything down evenly, each character sounds different from how it sounds at full speed, so you end up learning the wrong thing.

Farnsworth timing solves this. You send each character at a fast speed (say 18 WPM) so its rhythm is realistic, but you stretch the gaps between characters so the overall pace is slow enough to follow. This way you learn the true sound of each letter from day one and simply tighten the gaps as you improve. It's the method behind most effective Morse courses, and it's why the Learn Morse Code guide recommends "fast characters, wide gaps."

Why the sidetone sounds the way it does

Morse audio is usually a single steady tone switched on and off — commonly somewhere around 600–700 Hz, a pitch that's easy on the ear during long listening sessions. The on/off keying is shaped slightly at the edges so each beep doesn't produce an audible click. That's the clean "beep... beeep" you hear when you press play.

Once the timing clicks, reading by ear gets much easier — see how to read Morse code to put it into practice.