Dead Internet? A Third of New Websites Are AI-Generated, Says Stanford

In brief

• By mid-2025, 35% of newly published websites were AI-generated or AI-assisted, up from zero before ChatGPT's November 2022 launch.
• The confirmed effects are semantic contraction and artificial positivity—not misinformation or stylistic homogeneity, despite what most people believe.
• At 35% AI prevalence, model collapse risk shifts from a theoretical concern to an empirical one for the next generation of foundation models.

A new study has a number for how much of the internet is now AI-generated: 35%. That's the share of newly published websites classified as AI-generated or AI-assisted by mid-2025, according to research from Stanford University, Imperial College London, and the Internet Archive. The figure was essentially zero before ChatGPT launched in November 2022.

"I find the sheer speed of the AI takeover of the web quite staggering," Jonáš Doležal, researcher at Imperial College London and co-author of the paper, told 404 Media. "After decades of humans shaping it, a significant portion of the internet has become defined by AI in just three years."

The study, titled “The Impact of AI-Generated Text on the Internet,” drew on 33 months of website snapshots from the Internet Archive's Wayback Machine and used an AI text detector called Pangram v3 to classify each page.

The confirmed harms: vibes, not facts

Researchers tested six hypotheses about what AI content does to the web. Only two held up under data scrutiny.

The first: We’re turning into a horde of dumb NPCs acting in the same way… Or more scientifically put, the web is becoming less semantically diverse.

AI-generated sites showed pairwise semantic similarity scores 33% higher than human-written ones. The same ideas keep getting expressed in nearly the same ways.

The paper suggests the online Overton window may be narrowing, not through censorship or coordinated campaigns, but because language models optimize for outputs close to their training distribution.

The second: The web is getting aggressively cheerful.

AI content showed positive sentiment scores more than 107% higher than human content. Researchers tie this to the well-documented of LLMs—trained on human approval signals, they produce text that feels sanitized, friction-free, and relentlessly upbeat.