Detect GPT-3.5 AI text in seconds.
AI Checker spots GPT-3.5 content with sentence-level accuracy. Free detector for GPT-3.5 Turbo, GPT-3.5 Turbo 16k.
Every major GPT-3.5 version.
- GPT-3.5 Turbo
- GPT-3.5 Turbo 16k
Easy to detect.
Lightly edited and paraphrased GPT-3.5 text typically scores 5-15% lower. Heavy human editing reduces confidence further — always review the sentence-level breakdown.
How AI Checker spots GPT-3.5.
Five fingerprints that GPT-3.5 leaves behind, even after editing.
- 1Very low burstiness — most sentences hit 18-22 words
- 2Repetitive sentence openers ("It is", "This is", "There are")
- 3Generic vocabulary, low lexical diversity
- 4Conspicuous transition words at paragraph starts
- 5Tendency to repeat the prompt verbatim in the answer
The GPT-3.5 fingerprint.
GPT-3.5 is the easiest major LLM to detect — accuracy on unedited output is 99%+ on AI Checker. The model was tuned for helpfulness over stylistic variation, and its training data was less aggressively filtered than GPT-4's, leaving telltale repetitions. If you're an educator, publisher, or HR reviewer working with submissions before mid-2024, GPT-3.5 was the dominant tool used to generate text, and the pattern is unmistakable: uniform sentence length, generic phrasings, and conspicuous restatement of the prompt. Even paraphrased GPT-3.5 output remains 90%+ detectable because the vocabulary profile is so narrow. The one tricky case: when a human heavily edits a GPT-3.5 draft for tone, the sentence-level signal can drop to 60-70% — at which point you should rely on the sentence-by-sentence breakdown to find the few remaining AI-shaped passages.
What GPT-3.5 writing looks like.
There are several important reasons why one should consider the impact of artificial intelligence on modern society. It is widely acknowledged that AI technologies have revolutionized many industries. This is particularly true in fields such as healthcare, finance, and education. Furthermore, it is important to note that the ethical implications of AI deployment require careful consideration from policymakers, technologists, and the general public.
Frequently asked questions
Is GPT-3.5 detection free?
Yes. AI Checker offers a free tier for detecting GPT-3.5 text without signup. The free tier supports up to 10,000 characters per check with full sentence-level breakdown.
How accurate is GPT-3.5 detection?
On unedited GPT-3.5 output, AI Checker reaches 95-98% accuracy. Accuracy stays above 90% on lightly edited or paraphrased GPT-3.5 content. Heavy human editing reduces detection confidence — always review the sentence-level breakdown for nuance.
Can GPT-3.5 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 GPT-3.5 text in your own content.
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