Police 10-codes are the shorthand officers use over the radio — but there are a hundred of them, and nobody memorizes the list by reading it once. Use the lookup below to find any code in seconds, by its number or by what it means. Where we have a full guide to a code, the Details link takes you straight to it. Then take the quiz at the bottom of the page and see how many you actually know
Note: There is no single national 10-code standard. This lookup uses the widely published APCO meanings; your local department’s list may differ, and recruits should always learn their own agency’s version.
Showing all 100 codes
| Code | APCO meaning |
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No code matches that search. Try a shorter word, or clear the box to see the full list.
How to Use This Lookup
Type a code (for example 10-33) or a word from its meaning (for example “accident”) and the list filters as you type. The Details link beside a code opens our full article on that code — what it means, when officers use it, and how it differs between departments.
What Are Police 10-Codes?
Ten-codes were created in the 1930s and standardized by APCO (the Association of Public-Safety Communications Officials) so officers could say more with less: radio channels were crowded, reception was poor, and the first syllable of a transmission was often lost — the “ten” prefix gave the receiver a moment to start hearing before the important number arrived. The system spread across American policing and became famous worldwide through trucker CB radio and police TV shows.
Why Meanings Differ by Department
APCO published a standard list, but nothing forced departments to adopt it unchanged, so agencies adjusted codes to local needs over decades. After joint operations exposed how confusing that could be, federal guidance encouraged plain language for multi-agency work, and some departments dropped most codes altogether. The core codes — above all 10-4 — survived everywhere; the rest of the list is where the differences live.
The Codes Every Recruit Learns First
- 10-4 — Acknowledgment (OK)
- 10-7 — Out of service
- 10-8 — In service
- 10-9 — Repeat
- 10-20 — Location
- 10-33 — Emergency traffic
- 10-50 — Vehicle accident
- 10-76 — En route
- 10-78 — Need assistance
- 10-99 — Wanted or stolen indicated
Now Test Yourself
Reading the list is passive. Recalling meanings under pressure is what makes them stick — so run the quiz: ten random codes, four possible meanings each, instant corrections.
Test Yourself: 10-Codes Quiz
Ten random codes from the list above. Pick the right meaning for each one — no sign-up, and your answers never leave your browser.
What does this code mean?
Learn the codes your own academy or department actually uses, treat this page as your quick reference, and come back to the quiz whenever you want a refresher — scanner listeners use it too.
10-codes questions, answered
Do all police departments use the same 10-codes?
No. There is no single national 10-code standard. This page uses the widely published APCO list, but many departments change individual codes — 10-50 alone can mean a vehicle accident, a traffic stop or something else entirely depending on the agency. Always learn your own department’s list.
What does 10-4 mean?
10-4 means “acknowledgment” — the officer is saying OK, understood. It is the most universal of all the 10-codes and the one almost every agency uses the same way.
Are 10-codes being phased out?
Partly. After communication failures between agencies, federal guidance has pushed departments toward plain language, and some agencies have dropped most codes. Others still use them every day. In practice, most officers today mix plain speech with a handful of common codes like 10-4.
How should I learn 10-codes for the police academy?
Start with the roughly twenty codes used constantly — 10-4, 10-7, 10-8, 10-20, 10-33, 10-50 and 10-78 are good first targets — then use the lookup above to check the rest, and run the quiz until you score 10 out of 10 twice in a row. If your academy or department publishes its own list, learn that version.
Does the quiz store my answers?
No. The quiz runs entirely in your browser. Your answers and score are never sent to our servers or stored anywhere.
Keep reading on Police Pathfinder
- The most common police 10-codes — the short list every recruit should learn first
- Police codes list — the full code list in article form, with explanations
- What does 10-4 mean? — the most famous police code, explained
- Police scanner codes — what you are hearing on the scanner, decoded