F in Morse Code
F is ..-. - di-di-dah-dit, 9 units, 540 milliseconds at 20 words per minute.
At this speed the screen flashes more than three times per second. If you are sensitive to flashing light, set the speed to 7 WPM or lower.
Advanced settings
..-.
Press play in the box above - F is already in it.
How long F takes
F is 3 dots and 1 dash. With the gaps that comes to 9 units, number 13 of 26 by length.
- 5 WPM: 2,160 ms
- 13 WPM: 831 ms
- 20 WPM: 540 ms
The arithmetic behind them is on the timing page.
What F gets confused with
4 characters sit one element away from F:
- C
-.-.- a dash in first place instead of a dot - H
....- a dot in third place instead of a dash - P
.--.- a dash in second place instead of a dot - U
..-- the last dot missing
F in the tree
- Built from:
.= E,..= I and..-= U, then..-. - Carries on into: no other letter - a leaf of the tree
- Backwards:
.-..= L - Koch position: 16 of 26
The tree shows the whole shape, the trainer teaches it by ear.
Why F has this code
F makes up about 2.2 per cent of English text, which is number 16 of 26 by frequency, against number 13 by length. Close enough that the code is doing its job for this letter.
The lengths were set by counting, not by theory - the alphabet page has that story.
F in American Morse
The American code, used on the landline telegraph until the 1920s, wrote F as .-. instead of ..-.. That sequence is R in the international code, so the same rhythm meant two different letters depending on which side of the Atlantic you were sitting.
The full table has the other ten.
Frequently asked questions
-
What is F in Morse code?
..-.- 3 dots and 1 dash, spoken di-di-dah-dit. -
How long does F take to send?
9 units: 540 milliseconds at 20 words per minute, 2,160 at 5.
-
Which letters sound like F?
C, H, P and U - each one element away from
..-..