The short answer: SEO earns you a position in a ranked list of links on search engines. AEO earns you a mention inside AI-written answers on tools like ChatGPT and Perplexity. GEO is, for practical purposes, the same discipline as AEO under its research-world name. You don't choose between them — about 80% of the work is shared, SEO is the foundation the other two stand on, and the remaining 20% is cheap to add once the foundation is right.
The three, side by side
| SEO | AEO | GEO | |
|---|---|---|---|
| Stands for | Search engine optimization | Answer engine optimization | Generative engine optimization |
| The prize | A high position in a list of links | Being named inside the answer | Being cited by generative engines |
| Where it plays out | Google & Bing results pages | ChatGPT, Perplexity, Copilot, AI Overviews | Same surfaces; research framing |
| Slots available | ~10 per page, scrollable | A handful of named sources | A handful of named sources |
| Measured by | Rankings, clicks, Search Console | Monthly probes, AI referrals | Monthly probes, AI referrals |
| Full guide | What is SEO? | What is AEO? | What is GEO? |
Where the work overlaps — and where it differs
The shared core is the site itself: real text machines can fetch, pages that open with direct answers to real customer questions, one consistent identity across the web, authority earned from reviews and mentions, and honest speed. Do that well and you're most of the way to all three finishes.
The differences are thin layers on top. SEO adds classic plumbing — sitemaps, canonical URLs, Core Web Vitals. AEO adds AI-crawler access and machine-labeled Q&A (FAQ schema). GEO adds citable specifics — statistics, quotations, sources — plus llms.txt and a monthly probe habit. None of these layers works without the core; all of them are cheap once the core exists.
Which do you actually need?
All three — but in order, because they stack. SEO first: AI answer engines retrieve from search indexes, so a site invisible to Google is invisible to ChatGPT's search too. AEO/GEO immediately after — not eventually — because answer surfaces are where a growing share of buying research now ends, the named-source slots are far scarcer than list positions, and most of your competitors haven't started. The order of operations is the 30-day plans in our three guides, run in sequence; the measurement is a probe list next to your Search Console habit.
Common questions
Is GEO just a new name for AEO?
Effectively yes. AEO is the practitioner term, GEO the research term, and the techniques are shared. Some split hairs — AEO for direct-answer boxes, GEO for long synthesized responses — but you'd do the same work either way.
Will AEO and GEO replace SEO?
No — they sit on top of it. Answer engines retrieve from search indexes, so SEO health is the entry ticket. What's changing is where the customer's journey ends: increasingly inside an answer rather than on a results page, which is why the named-source slots matter so much.
Do I need separate agencies for each?
No, and be wary of anyone selling them as separate mysteries. Roughly 80% of the work is one shared core; a team that does that core well can add the AEO/GEO layers in days. We grade all three as one Findability lens for exactly that reason.
Which should a small business start with?
Start with the shared core — it is simultaneously SEO, AEO, and GEO progress: answer-first pages for your five most-asked questions, consistent identity everywhere, honest speed, reviews. Then add the thin layers in a weekend each.
Start with a reading, not guesswork
The Grader's Findability lens measures how search and answer engines actually see your site — in plain English, every result labeled Measured or Estimated.
Grade my site The SEO & AEO audit