StealthGPT passed GPTZero on 92% of texts (46 of 50) in HumanizerEval's October 2026 review, where every output was scored through GPTZero's API. GPTZero is among the most widely adopted AI detectors in general, built on perplexity and burstiness signals that distinguish human from AI writing. StealthGPT's humanization engine is specifically designed to shift these signals.
The detector
GPTZero is an AI content detection tool developed by Edward Tian and launched in January 2023, widely adopted across K‑12 and university settings. It analyzes text for perplexity, how predictable each word choice is given the surrounding context, and burstiness, how much sentence complexity varies throughout a document. AI writing tends to score low and uniform on both metrics; human writing tends to score higher and less predictably.
Benchmark
StealthGPT ranked #1 of 11 humanizers in HumanizerEval's October 2026 review.
HumanizerEval ran 11 AI humanizers, including StealthGPT Super, on the same 50 English texts, 364 to 997 words each. Every output was scored through GPTZero's API using its latest model, which measures perplexity and burstiness to produce an AI probability score. An output counts as a pass only when GPTZero's overall verdict is human, meaning a human score above 50%; mixed and uncertain verdicts count as fails. The review ran on October 22, 2026, and every per-text score is published in a public CSV.
StealthGPT passed GPTZero on 46 of 50 texts (92%). The remaining 4 texts were flagged or marked unclear. The average tool in the panel passed GPTZero on 47% of texts.
GPTZero pass rate, all 11 humanizers, October 2026
| Humanizer | ||
|---|---|---|
| StealthGPT Super | 92% | |
| WriteHuman | 90% | |
| Undetectable.ai | 86% | |
| Rephrasy | 70% | |
| Grubby | 68% | |
| RewriteAI | 54% | |
| Phrasly | 44% | |
| HIX Bypass | 6% | |
| BypassGPT | 4% | |
| Humbot | 0% | |
| Ryne | 0% | |
StealthGPT also passed all 6 detectors on 17 of 50 texts, more than any other tool.
StealthGPT Super passed 46 of 50 texts (92%) on GPTZero in HumanizerEval’s October 22, 2026 review.
Across the six-model panel, StealthGPT Super passed all six detectors on 17 of 50 texts. See the full rankings for the detector-by-detector breakdown.
GPTZero API · latest model setting. The review used 50 English texts per humanizer, 364–997 words each.
GPTZero accepts pasted text or a file upload and returns both an overall document result and sentence-level highlights. Its report also includes a written interpretation. For an essay or article review, that gives you two useful views: the full submission and the particular passages to examine. Keep the full draft open as you work through highlighted sections so the introduction, evidence and conclusion remain connected.
GPTZero’s browser extension includes a Google Docs Writing Report with a replay of the writing process. It opens from a document you can edit and can be shared by link. This is a separate view from scanning the final text: it helps a writer show how a document developed over time. For collaborative writing, agree which document version and report will accompany the final submission.
Yes. GPTZero documents both pasted-text and file-upload workflows. Its dashboard also supports longer texts and batches of files. Choose the input that best matches the document you are reviewing.
It accompanies the writing process rather than replacing the finished document. In the browser extension, open an editable Google Doc and select the Writing Report option; the report can then be shared as a link.
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Yes. In HumanizerEval's October 2026 review, StealthGPT passed GPTZero on 46 of 50 texts (92%) and registered as human written under GPTZero's perplexity and burstiness scoring.
GPTZero is an AI detection tool developed by Edward Tian in 2023, measuring perplexity and burstiness to distinguish AI writing from human writing across submitted documents. It is one of the most widely adopted detectors in K‑12 and university settings and offers both a free tier and paid plans for bulk document scanning. GPTZero can be contrasted closely with Scribbr, which also primarily serves AI detection in academic settings.
StealthGPT's AI humanizer rewrites AI generated content to introduce the structural variation, lexical diversity, and natural unpredictability that distinguish human writing from AI output. StealthGPT's AI humanizer is trained to target the specific signals each major detector uses and is continually updated as those detectors evolve.
HumanizerEval reruns its benchmark every month, and StealthGPT is tested in every review. The latest GPTZero result is 92%, from the October 2026 review. See HumanizerEval for the newest numbers.
In HumanizerEval's October 2026 review, StealthGPT passed Pangram on 88% of texts, GPTZero, Originality.ai Turbo and Winston AI on 92% each, ZeroGPT on 84% and Originality.ai 5.0 on 34%, for an 80.3% average bypass rate and the #1 rank among 11 humanizers. It passed all six detectors on 17 of 50 texts.
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