OK in Morse Code
Five dashes, one dot. “OK” is short, punchy, and has a deeper connection to Morse code than almost any other word — the telegraph helped make it famous.
How to write “OK” in Morse code
OK in International Morse code is −−− −·−:
It's a dash-lover's word: six signals, five of them long. O is the heaviest letter in the system — three full dashes — and K answers with its confident dash-dot-dash. Both patterns are easy to find on the Morse code alphabet chart, and because they're so dash-dominant, OK stands out clearly even in noisy conditions.
How it sounds
In operator speech: dah-dah-dah dah-di-dah. Slow, steady, unmistakable. Type OK into the Morse code translator and press Play — you'll hear why operators liked it: there's nothing hurried about it, and nothing that melts into static.
OK and the telegraph: a real love story
“OK” first appeared in print in 1839 as a jokey Boston abbreviation of “oll korrect.” What turned a local fad into a global word was, in large part, the telegraph. Operators needed a short, unambiguous way to confirm that a message had been received correctly — and OK was perfect: two letters, distinctive rhythm, hard to confuse with anything else. By the late 1800s, railway telegraphers across America were acknowledging train orders with OK, embedding it into official procedure. The word and the wire grew up together — more of that era in our history of Morse code.
The single-letter shortcuts
As traffic grew, operators trimmed even OK down. In amateur radio shorthand, R (·−·) means “received and understood,” and the letter K (−·−) sent alone means “go ahead — your turn to transmit.” That's why K closes so many radio exchanges to this day. So within this one little word you get two of the most useful prosigns in Morse: learn OK and you've learned half the etiquette of a radio conversation. Compare the confirmations on our yes in Morse code page.
Practice pairing
OK pairs naturally with YES and NO as an acknowledgement set: one person taps a question, the other confirms with OK. Because it's only six signals, most people can send it reliably within minutes. Try it by sound, then switch the translator to flash mode and send it by light — and keep building vocabulary with our common words and phrases.
Try it yourself
Open the Morse code translator, type OK, and press Play to hear it — or turn on the flash and vibrate options to see and feel the rhythm. You'll find more everyday examples on our common Morse code words page, and a full study plan in the guide to learning Morse code.
Frequently asked questions
OK is −−− −·− — O (three dashes) then K (dash-dot-dash). Six signals, five of them dashes. Hear it in the translator.
Sent alone, K (−·−) means “go ahead — your turn to transmit.” It’s one of the oldest and most-used prosigns in radio.
It helped enormously. OK started as an 1839 Boston newspaper joke, but telegraphers adopted it as their standard “message received” confirmation — short, distinctive, hard to garble — which pushed it into everyday language.
Play OK in Morse code
Type it, hear the authentic tones, flash it as light, or download it as audio — free in the translator.
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