New study from UC Berkeley and Univ of Washington found that about 24% of crawlable webpages held AI-generated or AI-edited text by August 2026, up from almost none before 2022.

They sampled 5.1M pages from Common Crawl snapshots spanning 2019 to 2026, in every language. A statistical model corrected for each detector's false alarms and misses, using pre-2022 pages as a near-AI-free baseline.

Yearly growth nearly doubled, from 4.6 points between early 2023 and early 2025 to 8.1 points after that. Small, little-linked sites drove 78.8% of the rise, while the most central sites were least likely to have AI text.