Study: AI Books Flood Amazon — a Third of New Bestsellers
New research finds AI-generated e-books now make up about 31 percent of new top-25 entrants on Amazon — and are dragging down human authors' earnings.
Illustration · AI-generated (AI IN LIFE)
Researchers analyzed 14,419 self-published e-books from January 2023 through March 2026, running full texts through an AI detector (Pangram v3.3, with a reported 0.04 percent false-positive rate).
At a glance
- 31% of new top-25 entrants are AI-heavy, per the study (previously near zero)
- 14,419 self-published e-books analyzed (Jan 2023 – Mar 2026)
- Catalog grew 38-fold; quarterly revenue only 9-fold
- AI-heavy titles: 20% of the catalog but only 12.1% of sales
- Top AI pseudonym: $1.7 million in revenue across eight titles
Researchers analyzed 14,419 self-published e-books from January 2023 through March 2026, running full texts through an AI detector (Pangram v3.3, with a reported 0.04 percent false-positive rate). The finding: the share of AI-heavy titles among new top-25 entrants rose from near zero to about 31 percent.
The flood dilutes the market: the catalog grew 38-fold over the study period, while quarterly revenue grew only 9-fold. In seven of eight genres, revenue per title fell even for books without AI text.
At the same time, AI books individually underperform: titles with substantial AI content make up about 20 percent of the catalog but only about 12 percent of sales. Human-written books, at roughly 63 percent of the catalog, generate about 72 percent of revenue.
The scheme can still pay off: the sample's top-earning AI pseudonym made $1.7 million across eight titles, and the best single AI book brought in $643,000 on more than 80,000 copies sold.
For human authors it is a double squeeze: more competition for visibility and falling revenue per title — while platforms like Amazon still enforce no AI disclosure toward buyers.
FAQ
How were AI books identified?
With the Pangram v3.3 detector on full texts; the study reports a 0.04 percent false-positive rate. Detectors remain imperfect nonetheless.
Do AI books earn more than human ones?
Per title, usually not — they undersell. But their sheer volume drags down everyone's revenue.
Does Amazon require AI labeling?
There is no enforced disclosure to buyers so far; authors only have to declare AI use internally to Amazon.
