About 33% of New Bestsellers Contain AI-Generated Content

A new study shows that about 33% of new books on Amazon's bestseller list contain AI-generated content. Researchers randomly sampled 14,419 self-published novels from 2023 to March 2026 and used AI detection tools to scan full texts. About 20% of samples had at least 25% AI-generated text, classified as "substantial AI content."

Romance, sci-fi, and thriller genres are all affected. AI-generated novels now make up about 20% of total novel sales in 2026. The number of novels surged 38 times in three years, but quarterly revenue only grew 9 times, showing AI content dilutes market value.

The study says AI content lowers average income for human authors and pushes their works down bestseller rankings, causing continuous loss of market share.