Answer Engine Optimization (AEO): the reference wiki

Answer Engine Optimization (AEO) is the work of making your content easy for answer engines (Google AI Overviews and AI Mode, ChatGPT search, Perplexity, Microsoft Copilot, Gemini, Claude and voice assistants) to find, trust and cite. Almost all of it is good SEO: crawlable pages, clear answers, real expertise and accurate entity information. What is new is where the answer appears and how you measure it.

AEO.wiki explains how answer engines retrieve and cite web pages, what each vendor actually documents, and which tactics are backed by evidence. Every factual claim links to a primary source or a published study, and every tactic carries an evidence label:

Vendor-documented the engine’s own documentation says so · Independent study a published study found it · Practitioner practice common practitioner practice, not confirmed by vendors · Not supported contradicted by vendors or unsupported.

Key facts (September 2026)

• Google says its AI features use retrieval-augmented generation (grounding) and “query fan-out” over the normal Search index, and that optimizing for them “is optimizing for the search experience, and thus still SEO.”^[1]
• Since August 31, 2026 every Search Console property has a Generative AI performance report and a control to include or exclude a site from AI Overviews and AI Mode.^[2][3]
• In Pew Research Center’s March 2025 browsing data, users clicked a traditional result in 8% of visits when an AI summary appeared, versus 15% without one.^[4]
• OpenAI, Perplexity and Anthropic each document separate crawlers for search and for model training, so you can allow one and block the other.^[5][6][7]
• No major engine has confirmed using llms.txt; Google says Google Search ignores it.^[1]
• Google stopped showing FAQ rich results on May 7, 2026; HowTo rich results were dropped in 2023.^[8][9]

Start here

Engine by engine

Do the work

Reference and tools

Use the robots.txt builder to write AI crawler rules, the fan-out planner to map the sub-questions a topic raises, the three-part glossary, the FAQ, a summary of published research, and a neutral list of tools and resources.

Who writes this

AEO.wiki is written by Simon White, “The SEO Fire Fighter” and co-founder of Local Blitz, with AI assistance and human review. Read the editorial policy for how pages are researched, sourced and corrected. The sister site SeniorLiving.wiki is built on the same principles; see the case study.

See also

• What is AEO?
• Engine comparison
• AEO checklist
• Studies & papers
• Glossary A–E
• FAQ

References

Pages accessed September 28, 2026 unless a date is given. See all sources and our editorial policy.

1. ^ "Optimizing your website for generative AI features on Google Search". Google Search Central. Added May 15, 2026; last updated July 10, 2026.
2. ^ "Generative AI performance report (Search)". Search Console Help. Rolled out to all sites by August 31, 2026.
3. ^ "Search generative AI control". Search Console Help. Rolled out to all sites by August 31, 2026.
4. ^ "Google users are less likely to click on links when an AI summary appears in the results". Pew Research Center. Published July 22, 2025; March 2025 browsing data.
5. ^ "Overview of OpenAI Crawlers". OpenAI Platform documentation.
6. ^ "Perplexity Crawlers". Perplexity documentation.
7. ^ "Does Anthropic crawl data from the web, and how can site owners block the crawler?". Anthropic (Claude Help Center).
8. ^ "Latest Google Search documentation updates (changelog)". Google Search Central. Entries for May–June 2026.
9. ^ "Changes to HowTo and FAQ rich results". Google Search Central Blog. Published August 8, 2023, with later updates.