Detect ChatGPT AI text in seconds.
AI Checker spots ChatGPT content with sentence-level accuracy. Free detector for GPT-3.5, GPT-4, GPT-4o, and 1 other ChatGPT variants.
Every major ChatGPT version.
- GPT-3.5
- GPT-4
- GPT-4o
- GPT-4 Turbo
Medium difficulty.
Lightly edited and paraphrased ChatGPT text typically scores 5-15% lower. Heavy human editing reduces confidence further — always review the sentence-level breakdown.
How AI Checker spots ChatGPT.
Five fingerprints that ChatGPT leaves behind, even after editing.
- 1Predictable sentence cadence (low burstiness)
- 2Frequent transitional phrases ("Furthermore", "In conclusion")
- 3Uniform mid-length sentences (15-25 words)
- 4Tendency to enumerate ideas in 3s
- 5Hedge phrases like "It's important to note"
The ChatGPT fingerprint.
ChatGPT is the most-detected AI writing on the web because it's also the most-used. OpenAI's RLHF training optimizes for clarity and helpfulness, which produces a recognizable rhythm: balanced clauses, signposted transitions, and tidy 5-paragraph structures. The cost of this clarity is predictability — and predictability is exactly what AI Checker measures via perplexity. AI Checker reaches 98%+ accuracy on unedited ChatGPT output across GPT-3.5 through GPT-4o. Detection accuracy stays above 90% even when users prompt ChatGPT to "write more casually" — the underlying token-probability shape persists. The hardest variant to flag is GPT-4o with custom system prompts that explicitly instruct sentence-length variation; expect 80-85% accuracy there. Sentence-level breakdown is critical for ChatGPT detection since most submissions are mixed authorship: a human draft polished by ChatGPT, or vice versa.
What ChatGPT writing looks like.
Artificial intelligence has fundamentally transformed the way we approach content creation in the modern digital landscape. Through the use of sophisticated language models, machines can now generate coherent, contextually relevant text that closely mirrors human writing patterns. Furthermore, this technological advancement has raised important questions about authenticity, attribution, and the evolving role of human creativity in an increasingly automated world. It is important to note that while these tools offer significant productivity benefits, they also present challenges for educators, publishers, and content moderators who must distinguish between human and machine-generated work.
Frequently asked questions
Is ChatGPT detection free?
Yes. AI Checker offers a free tier for detecting ChatGPT text without signup. The free tier supports up to 10,000 characters per check with full sentence-level breakdown.
How accurate is ChatGPT detection?
On unedited ChatGPT output, AI Checker reaches 95-98% accuracy. Accuracy stays above 90% on lightly edited or paraphrased ChatGPT content. Heavy human editing reduces detection confidence — always review the sentence-level breakdown for nuance.
Can ChatGPT be used in a way that avoids detection?
Heavy paraphrasing and manual editing can lower detection scores, but multi-signal detection (perplexity, burstiness, lexical fingerprinting) usually still catches at least one signal. AI Checker reports a probability rather than a verdict — treat scores as evidence, not proof.
Does AI Checker detect all OpenAI models?
Yes. AI Checker is calibrated for every major model from OpenAI, including the latest variants. We retrain on each major release to keep detection signatures current.
Is my submitted text private?
Yes. Text submitted to AI Checker is processed in memory and is not used to train models. We do not sell or share your content. Free tier submissions are not stored beyond the immediate analysis.
Detect content from other AI models
AI Checker covers every major LLM. Pick a model to see its specific detection profile.
Spot ChatGPT text in your own content.
Free, instant, sentence-level breakdown. No signup.