Over a third of web pages published since ChatGPT launch show signs of AI authorship

A new study from Pew Research has found that over one-third of web pages published since the release of ChatGPT show signs of AI authorship or substantial AI editing. The report, released on Thursday, analyzed nearly half a million English-language web pages collected from the past five years, starting a couple of years before ChatGPT’s November 2022 launch. Pew used Open Pangram’s technology to detect AI-written or heavily edited content. In a random sample of 10,000 web pages collected in July 2026, around 10% showed significant signs of AI authorship. However, this sample included older pages that predated AI writing tools, so Pew filtered out these to focus only on pages published after ChatGPT’s release. In this subset, over one-third (35%) of the pages showed signs of AI authorship. The study also found that .com domains had AI authorship rates around 10 times higher than .edu or .gov domains, which were both around 1%. .org domains had a 4.6% rate. The analysis acknowledges potential misclassification by AI detection tools but suggests the data is directionally accurate. Additionally, Pew noted an increase in other indicators of AI authorship, such as the use of em dashes, Oxford commas, and specific phrasing like 'it’s not X, it’s Y'.