Farnsworth spacing: what it is and when to drop it
Farnsworth spacing is a way of sending Morse code in which each character is sent at full speed, but the gaps between characters and between words are made longer. The letters sound exactly as they will at real speed, and the extra silence gives you time to name each one. You drop it gradually, once you copy well at your current spacing, until the gaps are back to standard length.
The technique is usually credited to Donald R. Farnsworth. It is one of the most useful tools a learner has, and one of the easiest to lean on for too long.
Character speed and effective speed
Farnsworth timing has two speeds, and it helps to keep them apart:
- Character speed is how fast each character is sent: the length of its dits and dahs and of the short gaps inside it.
- Effective speed is the overall rate in words per minute once the stretched gaps are counted. It is what you would measure if you timed a minute of the sending.
With standard timing the two are equal. A dit is 1 unit, a dah 3, the gap inside a character 1, the gap between characters 3 and the gap between words 7, all at one speed. With Farnsworth timing, the effective speed is set lower than the character speed, and only the gaps between characters and words grow to make up the difference.
Two things do not change. Inside each character, the dits, dahs and gaps keep their 1, 3, 1 proportions at the character speed, so A, .-, sounds exactly like A at that speed. And the stretched gaps grow together, keeping their 3 to 7 proportion, so a word gap still sounds longer than a letter gap.
What the gaps look like in practice
The usual way to work out the stretched gaps starts from PARIS, the standard word for measuring speed. At an effective speed of 8 WPM, for example, PARIS has to take 7.5 seconds, an eighth of a minute, just as it would with standard timing at 8 WPM. Its letters and the gaps inside them take 31 units at the character speed. Whatever time is left is shared among the four gaps between its letters and the gap after it, in the 3 to 7 proportion.
Here is what that gives with the characters at 18 WPM, where a dit lasts about 67 ms and a dah 200 ms:
| Effective speed | Gap between characters | Gap between words |
|---|---|---|
| 5 WPM | about 1.57 s | about 3.66 s |
| 8 WPM | about 860 ms | about 2.00 s |
| 10 WPM | about 620 ms | about 1.45 s |
| 13 WPM | about 400 ms | about 940 ms |
| 15 WPM | about 305 ms | about 710 ms |
| 18 WPM (standard) | 200 ms | about 467 ms |
The last row is ordinary standard timing: the two speeds are equal, and nothing is stretched. Every row above it uses the same letters, at the same speed; only the silences differ. At 8 WPM effective, the gap between characters is more than four times the 200 ms it would be with standard timing at 18 WPM. That is a lot of time to think, which is the point, and also the danger.
For the arithmetic behind the speeds themselves, see Morse code timing: the 1, 3, 7 rule.
Why stretching only the gaps helps
The alternative, slowing everything down, changes the sound of every letter. At 5 WPM a dit lasts 240 ms and a letter such as H, ...., takes 1.68 seconds: a row of separate beeps that almost asks to be counted. Counting works at that speed and then fails as soon as you go faster, and the counting habit has to be unlearned.
Farnsworth spacing keeps the letters fast, so each one arrives as a single shape you learn to recognize as a whole, and puts the slowness where it does no harm: in the silence. When you speed up later, the letters already sound right. Only the gaps shrink, and nothing you learned has to be relearned.
It pairs well with the Koch method, which also insists on full character speed from the start. Koch with some Farnsworth spacing in the early weeks is gentler than pure Koch, and keeps what matters most about it.
The trap: staying on it too long
The extra gap is time to think, and thinking is the habit you are trying to lose. Spend months at a wide spacing and you can get very good at a slow process: the letter ends, you name it in the silence, and the next one arrives just as you finish. That process does not survive standard spacing, where the next character starts 3 units after the last one ended.
Signs you have stayed too long:
- You copy cleanly at your current spacing, but fall apart when the gaps shrink even slightly.
- You name each letter only after it has ended, using the silence to do it.
- Words never form as you listen; you hear a string of letters and only read the word on the paper afterwards.
- Your effective speed has not moved in weeks, though your accuracy is high.
The sign that you are ready to move on is the opposite. You find yourself waiting in the gaps: the letter is named before the silence is half over, and the silence starts to feel long.
How to close the gap
- Keep the character speed fixed. Change one number at a time. If you raise the character speed and the effective speed together, you cannot tell which change is causing trouble.
- Raise the effective speed in small steps. A WPM or two at a time, and only once you copy reliably at the current setting. About 90 percent correct, the Koch method’s rule, is a fair bar.
- Expect a dip after each step. Accuracy falls for a few sessions and then recovers. If it has not recovered after a week, step back one WPM, then try again.
- Take the last step in one go. When the effective speed is within a few WPM of the character speed, only a fraction of a second of extra silence remains in each gap. Switch to standard spacing and stay there.
- Mix in standard spacing early. Now and then, before you are ready, copy a short session at standard spacing. You will miss more, but the change will not be a shock when it comes.
- After that, speed up both together. Once you copy at standard spacing, raise the speed with the gaps at standard length, or raise the character speed first with some Farnsworth spacing and close it again. Raising your Morse speed has more on the size of each step.
Your own sending is a separate question. Farnsworth spacing is a listening aid. When you send, aim for standard spacing, with letter gaps of 3 units and word gaps of 7, so the person copying you hears clean, readable Morse.
Setting it on a Mac
Dot & Dash starts this way out of the box: a new install sends characters at 18 WPM with Farnsworth spacing at 8 WPM, the 8 WPM row of the table above. In Settings, General you can set the speed anywhere from 5 to 40 WPM and the Farnsworth spacing below it, so you can close the gap one step at a time as your copy improves.
Questions
Is Farnsworth spacing the same as sending slowly?
No. Sending slowly stretches everything, the dits and dahs included, so every letter changes its sound. Farnsworth spacing keeps the letters at full speed and stretches only the gaps between them.
Does Farnsworth spacing change the gaps inside a letter?
No. The gap between the dits and dahs of one character stays 1 unit at the character speed. Only the gaps between characters and between words grow.
When should I stop using Farnsworth spacing?
When your effective speed is within a few WPM of your character speed and you copy reliably at it. At that point, switch to standard spacing and keep it.
What character speed should I use with Farnsworth spacing?
One fast enough that you cannot count the dits and dahs in a letter. Choose it once, keep it while you close the gaps, and raise it only after you copy well with standard spacing.