AI Code Detector
Paste code — or the words around it — and DetZero scores how strongly it shows AI writing patterns, with the driving parts highlighted. Free, no sign-up, and your code is never stored. Read the honesty note below before you rely on a result.
Read this first: what this tool can and can't do
The honest version: DetZero's engine is a text-pattern model. It was trained on prose — essays, articles and similar writing — not on source code, and it is not a code-specialised model. We claim no code-specific training and publish no accuracy figures for code, because we have not measured any we would stand behind.
What that means in practice: a result on code is indicative pattern analysis, nothing more. The signal is strongest on the prose that surrounds code — comments, docstrings, documentation, commit messages, pull-request descriptions, and mixed code-and-prose files — because that is the kind of text the model actually knows. Bare, idiomatic code with few comments gives the weakest signal and can score in either direction. Use a high score as a reason to look closer and ask questions, never as proof — in coursework, hiring or anywhere else.
Where people use it
Code review
A pull request that reads unlike the author's usual work — uniform comment style, textbook-perfect docstrings. Check the description and comments first; that is where the signal lives.
Coursework
Programming assignments increasingly arrive with an AI first draft underneath. A check can tell you which submissions deserve a conversation about how the code works — not a verdict.
Hiring tasks
Take-home exercises are easy to outsource to a chatbot. Screening the write-up and commit messages helps you decide what to probe in the follow-up interview.
Open-source contributions
Maintainers now field drive-by pull requests generated wholesale by AI. Checking the PR description and the comments in the diff is a quick first filter before a human review.
How to get the most from a code check
Paste the words with the code. A function plus its comments and docstring carries far more signal than the function alone. Check several files rather than one snippet — a pattern across a submission means more than any single score. Compare against a known sample of the same person's hand-written work if you have one; a sharp style break is more telling than a raw number. And read the highlighting: the parts that score as AI-written are usually the generic, template-like comments — which is itself useful information, whichever way the overall score lands.
The engine underneath is the same ensemble described on our AI Detection Tool page, and the accuracy page publishes its measured results — note those figures are for prose, the task the model was trained and tested on, and are not code figures.
Frequently asked questions
Is this detector trained on code?
No — and any tool that implies otherwise should be pressed for its test data. DetZero's engine is a text-pattern model trained on prose. Applied to code it gives indicative pattern analysis, not a code-specific verdict, and we publish no accuracy figures for code.
What does it read best in a code submission?
The words around the code: comments, docstrings, documentation, commit messages, pull-request descriptions, and files that mix code with prose explanation. Those are prose, and prose is what the model knows. Pure idiomatic code, with few or no comments, gives the weakest signal.
Which programming languages does it work with?
You can paste code in any language — the model analyses text patterns rather than parsing a specific language, and it was not trained per-language. Treat the result as indicative for every language, and strongest wherever comments and documentation make up a good share of the sample.
Can I use the result as proof in a hiring or coursework decision?
No. A score here is a prompt to look closer — compare style against the person's known work, ask them to walk through the code — never evidence on its own. That is doubly true for code, where our analysis is indicative rather than measured.
Do you store the code I paste?
No. Your code is scored in memory on our own server and immediately discarded. It is never written to disk, never logged, and never used to train anything — pasting proprietary code here does not send it to any third-party AI service. See the privacy page.
How much code should I paste?
At least about 40 words' worth of text — a function or two together with its comments is a reasonable minimum — and up to 2,000 words per check. Longer samples that include comments and documentation give steadier results than a bare snippet.