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Morse Code Speed Trainer

Farnsworth does not slow the characters — only the gaps, to 23.5:1 instead of 3:1. A Koch trainer with audio and the timing laid out.

words per minute — Koch says start here and stay
below the character speed turns Farnsworth on
Koch order, hardest first
sent in five-character groups
Hz — 600 to 800 is the usual range
per cent — Koch's threshold is 90

Practice

then press Check, or just hit Enter
Press “Send a group” to start Audio stays in your browser — nothing is sent anywhere.
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What Farnsworth actually changes

Timing at each speed

The characters you are working on

Farnsworth does not slow the characters

The usual explanation of Farnsworth spacing is that it sends slow characters and speeds them up later. That is not what it does. A character sent at 18 words per minute with a five word per minute overall rate has a 66.7 millisecond unit — precisely the same unit as straight 18 words per minute. Every dit, every dah and every gap inside a character is identical. What stretches is the silence between characters, and nothing else.

So the argument between Koch and Farnsworth cannot be about character rhythm, because both send the same characters. It is about spacing rhythm, and there the distortion is severe rather than subtle. Real Morse leaves three dit-lengths between characters. At 18 over 5 it leaves 23.5, nearly eight times as much, and 83 per cent of the transmission is silence. The rhythm you rehearse at that setting exists at no speed anyone actually sends at, which is a genuine thing to have to unlearn — just not the thing people usually name.

There is a second cost that rarely gets mentioned: the extra silence has to come from somewhere, and it comes out of your practice count. A hundred characters at 18 over 10 takes about 103 seconds against 61 straight, so a fixed practice session gets you roughly half as many characters through your ears. Whether the extra thinking time is worth halving the repetitions is a real judgement, but it should be made knowing that is the trade.

How to use

  1. Start with two characters at 18 words per minute and leave the speed alone.
  2. Send a group, type what you hear, then check — do not read the answer first.
  3. Add one character whenever you clear ninety per cent, and only then.
  4. If you catch yourself counting dits, the speed is too low rather than too high.

Frequently asked questions

Does Farnsworth spacing slow the characters down?

No, and this is the most common misunderstanding about it. Farnsworth sends every character at the full target speed and stretches only the silence between them. A character unit at eighteen over five is 66.7 milliseconds, which is exactly what straight eighteen words per minute gives — every dit, dah and internal gap is identical. What changes is the pause afterwards.

What is actually wrong with Farnsworth spacing then?

The spacing itself, which is distorted far more than most people realise. Real Morse leaves three dit-lengths between characters. At eighteen over five it leaves 23.5, nearly eight times as much, and eighty-three per cent of the transmission is silence. You are rehearsing a rhythm that exists at no speed anyone sends at, and that rhythm has to be unlearned later.

How is a Morse word per minute defined?

By the word PARIS, which is fifty units long by construction — thirty-one units of marks and internal gaps, and nineteen of spacing between the characters and after the word. Sending PARIS five times a minute is five words per minute, which makes one unit exactly 1200 divided by the speed in milliseconds. It is a definition rather than an approximation.

What is the Koch method?

Start with two characters sent at your full target speed, copy random groups of them until you are ninety per cent accurate, then add a third — still at full speed — and repeat. The speed never changes; only the alphabet grows. Ludwig Koch found in the 1930s that students reached working speeds far faster this way than by learning slowly and speeding up.

Why does Koch start with K and M rather than E and T?

Because K and M are maximally distinctive — they differ in every element — while E and T are the two shortest and most confusable characters in the alphabet. Frequency order sounds sensible but pairs the hardest discrimination with the moment you are least equipped to make it. The Koch order is chosen for contrast, not for how often letters appear.

Should I learn Morse at five words per minute first?

It is the traditional route and it is the one most people who quit took. At five words per minute a dit is 240 milliseconds, which is slow enough to count consciously — and counting is a decoding habit that caps you around ten words per minute and then has to be broken before you can go faster. Learning at speed avoids building the habit at all.

What does the ninety per cent threshold actually prove?

More than it looks like, even at the start. With two characters in play a pure guess scores fifty per cent, so ninety requires genuinely recognising both rather than being lucky. As characters are added the guess rate falls — twenty per cent at five characters, five per cent at twenty — so the same threshold gets steadily harder to reach by accident.

How long does a practice session take?

A hundred characters at a straight eighteen words per minute runs about sixty-one seconds. The same hundred characters at eighteen over ten Farnsworth takes about a hundred and three, because the extra silence has to come from somewhere. A fixed-length session therefore gets you roughly half as many repetitions with Farnsworth on, which is a cost worth weighing.

What tone frequency should I use?

Somewhere between six hundred and eight hundred hertz suits most people, and the exact figure matters less than picking one and staying with it. Consistency helps because you are learning sound-shapes rather than pitches, and changing the tone mid-course adds a variable for no benefit. Some operators with hearing loss in a particular band shift deliberately to avoid it.

Why should I copy behind rather than write immediately?

Because trying to write a character during the gap after it is what makes the gap feel too short, and it is the bottleneck that stalls people around fifteen words per minute. Experienced operators hold one or two characters in their head and write while the next arrives. Farnsworth spacing lets you avoid learning that skill, which is the strongest argument against it.

What speed do I need for an amateur radio licence?

None, in most of the world. The international requirement was dropped in 2003 and national administrations followed over the next few years, so Morse is now something people learn because they want to operate that way rather than because a test demands it. Contest and DX operators commonly work at twenty-five to thirty-five words per minute.

Does the audio in this trainer go anywhere?

No. The tones are generated in your browser with the Web Audio interface, and what you type is compared locally against what was sent. Nothing about your practice leaves the page, there is no account and no session history is kept — closing the tab discards everything, which also means your progress is not stored between visits.

🔒 This tool runs entirely in your browser. Nothing you enter is uploaded, logged, or stored.