Morse Code Prosigns & Q-Codes

What Prosigns Are

A prosign (procedural signal) is a group of dots and dashes sent as one continuous, unspaced run — and instead of spelling text, it issues a command that structures the conversation: "end of message," "wait," "error," "distress." The famous SOS (...---...) is a prosign. So is .-.-. (AR, "end of message") and ...-.- (SK, "end of transmission").

Two things make prosigns special. First, the no-gap rule: the elements are run together with only 1-unit intra-character spacing, never the 3-unit letter gap — that's how the receiver knows it's a prosign and not ordinary letters. .-.-. as one group means AR ("end of message"); .- .-. with a letter gap means the letters A R. Second, most prosigns share their code with an ordinary character — AR is also the plus sign, BT is also the equals sign — and only context tells the receiver which meaning you intend. Written down, prosigns go in angle brackets or with an overbar: <AR>, <SK>, AR.

The Core Seven Prosigns

These seven are the working vocabulary of every morse conversation — and they're built into our translator (type <AR> and it encodes the run-together group). Press play to hear each one:

A typical contact ending looks like this: ... . . / - .... .- -. -.- ... / . ... / --- -- / -.-. --- -. - .- -.-. - / .-.-. / ...-.- — "SEE THANKS ES OM CONTACT <AR> <SK>". The AR closes the message; the SK closes the contact. Learn the rhythm of those two and you'll recognize the end of every morse conversation you ever hear.

How to Send Prosigns Correctly

• No internal gaps — ever. The whole group is sent with 1-unit spacing throughout. If you leave a 3-unit letter gap inside .-.-., the receiver hears "A R", not "end of message." This is the single most common prosign mistake.
• Write them in angle brackets. In text, <AR> / <SK> / <BT> is the standard notation. On paper or in old texts you may see an overbar instead (AR).
• Context decides shared codes. Mid-sentence, .-.-. is a plus sign; at the end of a transmission, it's AR. The receiver isn't guessing — position in the exchange makes it obvious.
• Don't invent prosigns. Running random letters together doesn't create a new prosign; it creates confusion. The set below is the established vocabulary — stick to it.
• SOS is special. It's the only prosign that's also a distress signal, and it's sent only in genuine distress. Full story: SOS in morse code.

Extended Prosigns: The Full Vocabulary

Beyond the core seven, these procedural signals appear in on-air practice, contests, and net operations. Every code below is a run-together group — no internal gaps. (A few, like AA and BK, aren't in our translator's built-in set, but they're genuine established prosigns.)

Notice the pattern: almost every multi-letter prosign is just two ordinary letters run together (AA = A+A, BK = B+K, CT = C+T, DO = D+O, SN = S+N). That's not a coincidence — prosigns grew organically out of abbreviation practice on the landline telegraphs, and the run-together sending is what promotes an abbreviation into a prosign.

Error Conventions: What to Do When You Mess Up

Everyone flubs a character on the key — even operators with 40 years on the air. Morse has a formal correction ritual:

1. Send <HH> — eight dots (........), no gaps. Some operators send even more dots for emphasis.
2. Resend the corrected word (or the last few words) immediately after.

That's the whole protocol. The receiver hears the error prosign and simply discards whatever came right before it. Example: you meant to send .--. .- .-. .. ... (PARIS) but fumbled the R — you'd send .--. .- .-. .-. .. ... ........ .--. .- .-. .. ... and the receiver reads "PARIS" once, cleanly.

Ham Abbreviations Glossary

Not prosigns, but you'll hear them in every contact: the shorthand vocabulary of the bands. These are sent as ordinary letters and numbers (with normal letter gaps) — they're abbreviations, not run-together commands.

String them together and a whole contact fits in a breath: -.-. --.- / -.-. --.- / -.. . / -- ----- .- .-- / -- ----- .- .-- / -.- — "CQ CQ DE M0ABC M0ABC K". That's a complete call to the world in about ten seconds.

Q-Codes: Questions and Answers in Three Letters

Q-codes are standardized three-letter codes (always starting with Q) that pack a whole question or statement into three dits and dahs. Add a question mark and it's a question; send it plain and it's a statement. They're sent as ordinary letters — no special run-together treatment — which makes them easy to learn and impossible to confuse with prosigns.

Q-codes were born for maritime and aeronautical radio, where operators might share no common language — --.- .-. -- means "interference" whether you speak English, Japanese, or Portuguese. That universality is why they've survived a century. The full official list runs to dozens of codes, but these twelve cover ~95% of what you'll actually hear.

Cut Numbers: Morse Shorthand for Digits

In fast contest exchanges, even five-element digits feel long — so operators "cut" them. Each long digit is replaced by a shorter letter code. The mapping is systematic: take the digit's code and keep only the distinctive end of it.

The classic example: the signal report 599 (..... ----. ----.) becomes 5NN (..... -. -.) — nearly half the sending time. You'll hear "5NN" in every CW contest on the planet. Cut numbers are a sending shortcut for speed; in normal conversation, send full digits. (Some operators also cut 0 to a long dash — context makes it clear.)

Frequently asked questions

Ready to Send Like an Operator?

Practice the prosigns by ear in the morse code trainer, drill your sending on a virtual straight key at morse code key, or look up any letter or number in the alphabet hub and numbers reference.