ChatGPT Detector
Wondering if something was written by ChatGPT? Paste the text below to get an instant likelihood score and see which sentences show the strongest AI signals.
This ChatGPT detector looks for the patterns large language models tend to produce — uniform sentence rhythm, predictable phrasing, and low variation (how detection works). It works on output from ChatGPT and other models alike.
The ChatGPT style signature — what the detector actually measures
ChatGPT's writing has statistical habits that separate it from human prose. The most telling is uniform sentence length: humans throw out a short sentence, then sprawl into a long one, while ChatGPT tends to keep every sentence in a paragraph at roughly the same length. Next come stock transitions — 'Additionally', 'Furthermore', 'In conclusion', 'Overall' — appearing on a regular beat, and a mechanical argument-evidence-summary structure repeated paragraph after paragraph.
ChatGPT also over-uses lists and balanced parallels: unprompted 'firstly/secondly/thirdly' breakdowns, and an insistence on presenting both sides of everything ('while X can be beneficial, it may also…'). Finally, there's the absence of specifics — instead of names, dates, numbers, and lived detail, sentences fill up with all-purpose modifiers like 'effective', 'comprehensive', and 'various'. This detector measures those signals sentence by sentence and converts them into a 0–100 score.
Human vs ChatGPT — a side-by-side example
Human: “I put off writing the talk for two days. Honestly, I was scared — I kept replaying the moment last semester when one question froze me solid. At 2 a.m. I finally tore up the script and started over.” Sentence lengths swing wildly, and the specifics (last semester, 2 a.m.) belong to one person's life.
ChatGPT: “Preparing an effective presentation requires systematic planning. Additionally, materials should be tailored to the audience's level of understanding. Finally, sufficient rehearsal can significantly improve the quality of the delivery.” Three near-identical sentence lengths, stock transitions, and not a single detail that couldn't apply to anyone. Paste both kinds of text into the detector above and compare the scores yourself.
Is this the same as a GPT detector?
Yes. 'ChatGPT detector', 'GPT detector', and 'AI detector' all describe the same job — estimating how likely a text was produced by a GPT-family model. This one page covers them all. Because it measures general AI writing patterns rather than fingerprinting one product version, it applies to GPT-4, GPT-5, and non-GPT models like Claude and Gemini as well.
The caveat: newer models imitate human variation better, so read high scores on recent-model output conservatively and treat every score as supporting evidence, not a verdict (why detectors flag human writing).
Frequently asked questions
Can this detect text written by ChatGPT?+
Yes. It estimates how likely text was AI-generated based on writing patterns common to ChatGPT and similar models, returning a 0–100 score with highlighted sentences.
Is a ChatGPT detector different from a GPT detector?+
No — they're two names for the same task: estimating whether text was produced by a GPT-family model. This page handles both, and it also works on output from Claude, Gemini, and other models.
Does it work on GPT-4 and GPT-5 text?+
It targets general AI writing patterns rather than a specific version, so it applies to newer ChatGPT models. Newer models are harder to detect, so scores are a signal, not proof.
What's the minimum length for a reliable check?+
Aim for at least 100 characters (roughly 15+ words). Below that there isn't enough signal, and scores get pulled toward the middle.
Can teachers prove I used ChatGPT with this?+
No. A detector score is not proof. It can produce false positives on human writing, so it should never be the sole basis for an academic accusation.
⚠️ Disclaimer: AI Killer results are probabilistic signals and are not 100% accurate. Detectors can flag human writing as AI, so do not use this as the sole basis for accusations of plagiarism, cheating, or academic misconduct.