Visibility index · United States

Online bookstores

20 AI answers to 5 prompts name 9 brands. Amazon leads with 22.5% of mentions; the top 3 hold 58.4%.

Level 3n = 20 answers5 promptsupdated Oct 25, 2026AI Mode5ChatGPT5AI Overviews5Gemini5

AI answers

5 prompts

Last run Oct 25, 2026

Brands seen

Top 3 hold 58.4%

n = 20 answers

Concentration

Moderate

HHI 1,572 · leader 22.5%

Leader

Amazon

22.5% of mentions

Avg. position #3.5

Top engine

AI Mode

25% of answers

4 engines sampled

Sources cited

n = 20 answers

What AI answers show

Brands and sources in the sampled answers

n = 20 answers5 promptsOct 25, 2026

Share of brand mentions in Online bookstores answers

+4 more brandsFree with an AI Rankia accountLog in to see all

n = 20 answers9 brands seen in total

Market concentrationModerate

FragmentedModerateConcentrated

HHI 1,572Leader 22.5%Top 3 58.4%

Moderately concentrated: the top 3 hold 58.4% of mentions; the leader 22.5%.

Every engine sampled