Pew study: one in ten web pages shows signs of AI authorship
Pew Research Center's Data Labs team ran nearly half a million web pages through an AI detector and found signs of AI authorship or editing in about 10% of them. Among pages published after ChatGPT's launch, that figure climbs to 35%. The study, published August 20, is the third major estimate of AI-generated text prevalence on the internet released in the past year.
The data shows a stark divide by domain type: .com pages show roughly 10 times more signs of AI authorship than .edu and .gov pages. On a six-month rolling average, the share sits at 9.35% for .com, 4.59% for .org, 1.03% for .edu and just 0.76% for .gov. In the pre-ChatGPT sample, all four domain types hovered around 1% or lower — since then, they've diverged sharply, with .com climbing the fastest.
Pew also tracked distinctive stylistic "markers": em dash usage rose from 5.79 per 10,000 words in early 2023 to 11.19 in early 2026, while use of the Oxford comma climbed 63%. Use of words common in AI-generated writing — like "delve," "interplay" and "testament" — more than doubled. But as Pew notes, none of these markers alone can definitively flag a single document — human writers use this style and vocabulary too; the finding is about ratios across large bodies of text.
Other studies put the figure much higher: SEO firm Graphite estimates that 49.9% of new English-language articles published in the first quarter of 2026 were mostly AI-generated. A not-yet-peer-reviewed study from Imperial College London, the Internet Archive and Stanford University concluded that by mid-2025, 35% of newly created websites were AI-generated or AI-assisted.
Why does this matter? Signs of AI text are concentrated above all in the commercial web — precisely where SEO professionals do most of their work. Pew's methodology also lumps together human-written text later edited by an AI tool with text generated by AI from start to finish, further blurring the line at a time when AI editing has become a standard feature in Google Docs and Microsoft Word. In the end, whether a page is accurate, useful and worth publishing can still only be determined one way — by reading it.
Related articles
Why marketers are chasing fandoms instead of audiences
Brands want to become part of culture rather than simply advertise to it — and they're finding their way in through fandoms. Why is the trend gaining steam, and how do you even measure it?
Brands Care About Fit, Not Follower Count — New Creator Marketing Research
New research from CreatorIQ shows brands rank brand fit above all else when choosing a creator to work with, placing follower count dead last. Yet pay still tracks follower count closely.
Google Now "Builds" a Full Interface Right in Search Results — What It Means for Site Owners
Google's generative UI technology is rolling out to AI Overviews: the search engine now builds an interactive calculator or visualization on the fly, based on your query. Google's own research shows what that means for websites.