GPT Detector
Check whether text was written by a GPT model. Paste it below to get an instant likelihood score and see which sentences carry the strongest AI signals.
This GPT detector measures the patterns GPT-based models tend to leave behind — predictable word choices and uniform sentence rhythm (how detection works). It applies to ChatGPT, GPT-4/5, and other large language models.
Sentence-level highlights
See the exact lines that read as AI.
Every major model
ChatGPT, Claude, Gemini — not just one.
Instant & free
No sign-up. Same text, same score.
Honest by design
A probability, never a false verdict.
Frequently asked questions
What is a GPT detector?+
A GPT detector estimates how likely text was produced by a GPT-based language model. It analyzes writing patterns and returns a 0–100 score with sentence-level highlighting.
Does it detect GPT-4 and GPT-5?+
It targets general GPT writing patterns rather than a specific version, so it applies to newer GPT models. Newer models are harder to detect, so treat the score as a signal, not proof.
Is the GPT detector accurate?+
No GPT detector is 100% accurate. False positives and false negatives both happen, especially on short or formal text. Use the result alongside your own judgment, never as the sole basis for a decision.
⚠️ 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.