Undetectable.ai

Undetectable AI (alternatively Undetectable.ai) is an artificial intelligence content detection and modification software designed to identify and alter artificially generated text, such as that produced by large language models.

Undetectable AI was developed by Bars Juhasz, a PhD student from Loughborough University, along with Christian Perry and Devan Leos. It was publicly released in May 2023.

Several studies have examined Undetectable AI:

• In July 2023, researchers from Magna Græcia University tested Undetectable AI against generative-text and plagiarism detection software. They found that texts processed through the software were significantly harder to detect as AI-generated.

• In November 2023, Erik Piller of Nicholls State University published a paper examining the ethical implications of Undetectable AI in professional writing contexts.

• In August 2023, researchers led by Christoph Bartneck investigated how Undetectable AI might affect data quality in online questionnaires. They found that while AI detection systems could identify ChatGPT-generated text, they were less successful with text processed by Undetectable AI.

• In October 2025, journalist David Gewirtz tested Undetectable AI's content detector to see if it could accurately identify AI-generated text who stated "it rated human writing (Test 1) as 60% likely AI, and all three AI writing samples as 75%, 76%, and 77% likely human. Ah, well, I guess Undetectable is "humanizing" its results, insofar as it's living up to the phrase "to err is human.".

• GPTZero

• Turnitin

• Copyleaks

• Content similarity detection

• "The software says my student cheated using AI. They say they're innocent. Who do I believe?" at The Guardian

• "The Risk of Artificial Intelligence in Education and AI Detection Tools" (PDF) at ResearchGate