Fact · Voice and AI
26percent
On OpenAI's challenge set of English texts, its AI text classifier correctly identified 26 percent of AI-written text as likely AI-written.
Checked against its source on October 17, 2026
In the source's own words
“our classifier correctly identifies 26% of AI-written text (true positives) as”
New AI classifier for indicating AI-written text (OpenAI, January 31, 2023, with July 2023 update), Jan Hendrik Kirchner et al., OpenAI, 2023, Limitations section of the post.
Open the original- What it measures
- The figure is a true-positive rate on a challenge set that OpenAI assembled for its own evaluation, measured when the classifier was launched in January 2023.
- What it does not show
- A true-positive rate of 26 percent means most AI-written text was not flagged. The test set was English only and is not a measure of any other detector, language or kind of writing.