Answer engine optimization (AEO): what it is and how to do it

What is answer engine optimization?

Answer engine optimization (AEO) is the work of making your content the source an answer engine uses. An answer engine does not return a list of links first. It returns a written answer, usually with a few cited sources. Google’s AI Overviews and AI Mode, ChatGPT search, Perplexity and Microsoft Copilot all work like this. AEO asks one question of every page: can a system find a clear answer here, lift it out and credit the page?

The idea is older than AI assistants. Google’s featured snippets pull a short answer from a page to the top of the results, and Google says its systems choose them automatically: you cannot mark up a page to become one. AEO extends that thinking to every system that writes answers.

AEO is one of several overlapping labels. Google’s optimisation guide says “AEO” stands for answer engine optimization and “GEO” for generative engine optimization, that you may see both used, and that the work is still SEO. Our GEO vs SEO comparison explains how the terms relate, and the generative engine optimization guide covers the research behind GEO.

How do answer engines pick their sources?

Nobody outside the vendors knows the full recipe, and a list of “ranking factors” stated as fact goes beyond what any vendor documents. These are the parts each one does publish.

Three gates follow from this: be crawlable, be retrievable for the sub-questions behind a prompt, and be easy to quote once retrieved. The first is covered by OpenAI’s crawler documentation, Perplexity’s crawler page and our guide to AI crawlers. The rest is what the next section is about.

Answer engine optimization: on-page patterns that help

These patterns make a passage easy to understand and lift. They are not secret signals. Microsoft’s guidance for AI search answers recommends direct one- or two-sentence answers, modular sections and tables, while Google says there is no requirement to break your content into tiny pieces and no ideal length. The principle behind both is that a reader, human or machine, should find the answer fast.

1. 1

   Put a question or a clear topic in the heading

   Headings that state the question people ask, such as “How long does a crawl take?”, give a retrieved passage context. Avoid vague labels like “Learn more”.

2. 2

   Answer in the first one or two sentences

   Lead each section with the direct answer, then add the detail. A passage that makes sense on its own survives being quoted out of context.

3. 3

   Keep one idea per section

   Short sections with clear boundaries are easy to retrieve. Do not split one topic across many thin pages, because Google warns that producing a page for every query variation can breach its scaled content abuse policy.

4. 4

   Use tables and lists where the content is a comparison or a procedure

   Give every option the same columns, so a fact can be lifted without losing its label. Use numbered lists for steps and bullets for parallel items.

5. 5

   Attach numbers to sources and dates

   Write “108 seconds, measured on 10 Oct 2026” instead of “fast”. Name the source of any figure and never invent a statistic or a quote.

6. 6

   Name entities consistently

   Use the same name for your company, product and people everywhere, and say what each one is where it first appears. Consistency helps readers and systems match the page to the right thing.

7. 7

   Show who wrote it and when it was updated

   Google’s guidance on helpful content asks whether it is clear who created a page and how. A visible author or organisation and an update date also help a reader judge whether to trust a cited page.

8. 8

   Keep the answer in the HTML

   Do not hide key answers in tabs, images or PDFs, and render them on the server. Google asks that important content is available as text, and Vercel’s December 2024 analysis found that crawlers such as GPTBot, ClaudeBot and PerplexityBot did not render JavaScript. Our guide to JavaScript SEO explains how to check.

A worked example: from vague to answer-first

This is how one section changes. The facts in the second version come from Serpel’s own audit of serpel.app on 10 Oct 2026, described in our SEO audit report example.

Does structured data help answer engines?

Less than the folklore suggests. Google says there is no special schema.org markup you need for its AI features, and its guide states that structured data is not required for generative AI search. Google still recommends structured data for rich results, as long as it matches the visible text. Microsoft’s guidance suggests adding JSON-LD to label content types such as products and events.

One change deserves a warning. Google announced in its search updates log that the FAQ rich result would no longer appear in Google Search from 7 May 2026, and the documentation was removed in June 2026. Earlier, in 2023, Google had limited FAQ rich results to well-known government and health sites, and said there was no need to proactively remove existing markup. So do not add FAQPage markup in the hope of an answer-engine boost. Write a visible FAQ section because readers ask follow-up questions, and treat any markup as a description of what is on the page. You can test markup with our free schema validator.

Which answer engine optimization tools do you need?

Be wary of tools that promise results. Google’s guide says no third-party tool has access to its internal ranking or AI systems and advises checking any tool’s advice against official guidance. Tools are useful for measurement and for finding technical problems. They fall into five groups, with no ranking implied.

Serpel covers the first and third rows. It asks ChatGPT with web search and checks Google AI Overviews for your prompts, and each crawl tests your robots.txt against 13 AI crawlers and looks for an llms.txt file. It does not query Perplexity, Gemini or Claude, so use their own tools for those.

How do you measure answer engine optimization?

Define a small set of numbers before you edit anything, and track them over the same prompts.

• Citation rate: the share of your checked prompts where an answer links to your domain.
• Mention rate: the share where your name or domain appears in the text. A cited answer counts as mentioned too.
• Cited competitors: the domains that are cited when you are not, which shows whom the engine prefers.
• Engine reports: impressions from Search Console’s Generative AI performance report, and citations from Bing’s AI Performance report.
• Crawler hits: requests from OAI-SearchBot, PerplexityBot and others in your logs, with their status codes.

Answers vary from run to run, so one check proves little. Take a baseline, change one page, wait for crawlers to return (OpenAI says search systems can take about 24 hours to adjust to a robots.txt change) and run the same prompts again. The GEO vs SEO guide shows how to combine the four measurement sources.

serpel ai add --project <project-id> --prompt "How long does a site crawl take?"
serpel ai run --project <project-id> --wait
serpel ai prompts --project <project-id>