X in Morse code

X is dash dot dot dash in International Morse code, said “dah-di-di-dah”. It has 4 elements and lasts 11 units, which is 660 ms at 20 WPM.

X on a timing ruler

Dots last one unit, dashes three, and the gaps inside the letter one unit each. The numbers under the ruler are the length of each part.

How to remember X

X is D with one more dash on the end.
-..- reads the same forwards and backwards.
Say it out loud as “dah-di-di-dah”. Learning the rhythm, not counting dots and dashes, is what lets you recognise it at speed.
X is character 41 of 41 in the Koch learning order. Practise it in the Koch trainer.

Letters that sound like X

These are the letters most often copied by mistake for X, and why.

Can you hear the difference?

Listen, then pick the one you heard.

X on the air

The ITU sends the multiplication sign as X, so 2×3 goes out as “2 X 3”.
XYL, “ex-young lady”, is traditional operator slang for a wife.

X at a glance

Morse code: -..-
Sounds like: dah-di-di-dah
Length: 11 units
At 20 WPM: 660 ms
NATO word: X-ray
Frequency in English: 0.15% (24th of 26)

American Morse is different. In the American (Railroad) Morse once used on US telegraph lines, X was .-..: dot, dash, dot, dot (International L). International Morse, the code used today, is -..-.

Sources: codes from ITU-R M.1677-1, the International Morse code standard; English letter frequencies from Robert Lewand’s analysis; American Morse from the historical US telegraph code.

Hear X at your speed