A citation in an AI answer is a link to a source page that an AI engine attaches to its response to show where information came from. It counts whether it appears inline, as a numbered reference or in a list of sources, and whether or not the answer names the page's owner.
A mention is different: it is a brand's name in the answer text, with or without a link. The two can occur separately, which is why they are counted separately.
How engines show citations
- ChatGPT. Answers that use web search may include citations that open the source when selected, and a Sources button, when available, lists the cited sources plus other relevant links.
- Perplexity. Each answer includes numbered citations linking to the original sources.
- Claude. When Claude uses information from the web, Anthropic says it gives direct citations so readers can check the sources.
- Google AI Overviews and AI Mode. Google calls them supporting links. A page is eligible only if it is indexed and eligible to appear in Google Search with a snippet.
How we count them
In our scans (methodology), a citation is one source URL shown in one answer, and sites are grouped by domain. The number per answer varies widely by engine.
| Engine | Answers | Third-party citations | Per answer |
|---|---|---|---|
| Perplexity | 552 | 11,131 | 20.2 |
| Claude | 552 | 4,377 | 7.9 |
| Google AI Overviews | 523 | 4,117 | 7.9 |
| Google AI Mode | 248 | 1,814 | 7.3 |
| ChatGPT | 552 | 2,598 | 4.7 |
| Grok | 552 | 2,481 | 4.5 |
| Gemini | 552 | 1,910 | 3.5 |
Why citations matter for AEO
A citation is the part of an answer that can send a reader to your page, and it points at a specific URL you can improve. Its weight depends on the engine: one of 3.5 sources in a Gemini answer is a much bigger slice of that answer than one of 20 in a Perplexity answer. What seven AI engines cite shows which sites each engine favors.
An example: the wrong kind of "cited"
One question in our scans is "how to get cited by ChatGPT". Perplexity and Claude answered it by citing APA Style's page "How to cite ChatGPT" 27 times between them (16 and 11). That page tells students and researchers how to reference ChatGPT output in a paper. The citations are real, but the page answers a different question.
Common misconceptions
- "A citation is an endorsement." It shows where information came from. The cited page may be off topic, as above, or may recommend a competitor.
- "Named means cited." An answer can name a brand without linking to it, so track both.
- "Citations are always accurate." OpenAI's help center warns that search results and citations can be incomplete, outdated or incorrect, and suggests opening the source to check that it supports the answer.
Engine-specific tactics are in how to get cited by ChatGPT and how to get cited by Perplexity.