GEO, Generative Engine Optimization, broke into the mainstream marketing literature in late 2024. Eighteen months later it's no longer a buzzword: AI Overviews shows up in up to 12.5% of Google queries, and Perplexity plus ChatGPT search together handle billions of queries per month. If you only do classic SEO, you're missing half the picture.
What exactly is GEO?
GEO is the practice of writing and structuring content so AI models (ChatGPT, Claude, Perplexity, Gemini, Google AI Overviews) cite your site when assembling answers. Not clicks-from-results, but mentions-in-answers. The goal is the same, be findable, but the mechanics differ.
The three biggest differences
1. Passages > pages
Google indexes pages and ranks them in ten blue links. LLMs cite passages, single paragraphs of 40-80 words. A page can rank position 8 in Google and still be the source for an AI Overview. What matters is whether your paragraph directly answers a question.
2. Consensus > backlinks
Google ranks by authority via backlinks. LLMs scan for consensus, does your brand show up consistently on Reddit, YouTube, review sites, and your own domain? Public citation data shows 46.5% of Perplexity's citations come from Reddit discussions. Backlinks still matter, but source diversity now weighs more.
3. Depth > keyword density
GEO tooling research shows: articles over 2,900 words average 5.1 AI citations, articles under 800 words average 3.2. Not longer than necessary, but: cover the topic fully or get passed by someone who did.
What stays the same?
Everything that made classic SEO strong remains foundational: technical health (crawlability, INP, schema), clear information architecture, trust signals (author, date, citations), and internal links that show what relates to what. Google AI Mode pulls from the same index as the blue links, those who rank well traditionally get pushed in AI Mode automatically.
Where do you start?
- Audit your top-5 pages: does every H2 open with a direct 40-60-word answer?
- Add an llms.txt and llms-full.txt to your site (5 minutes of work, 0 SEO risk).
- Implement Organization, LocalBusiness and FAQPage schemas as a baseline.
- Build brand presence on review sites and LinkedIn, consensus signal.
- Measure monthly: ask ChatGPT/Perplexity/Claude what they say about your brand.