# LLM Citation

When large language models (ChatGPT, Claude, Gemini, etc.) cite or reference a web page as a source in the answers they generate.

**LLM Citation (Large Language Model Citation)** is when large language models such as ChatGPT, Claude, Gemini, and Perplexity cite a web page as a source or quote from its content while generating answers to user questions.

LLM citation happens in two ways:

- **Citation from training data:** Content from the data the model was trained on is reflected in responses either directly or in paraphrased form. In this case, citing the source is not guaranteed.
- **Citation via live search:** The model performs a real-time web search for the user’s query and quotes from the results (such as Perplexity, ChatGPT Search, and Gemini). Here, source links are shown explicitly.

To earn LLM citation:

- Structure your content in a format that answers the question directly
- Use clear, concise, quotable sentences
- Increase credibility by adding source references and data
- Strengthen your brand entity (Wikipedia presence, industry directories)
- Optimize the content for different query variations

Measuring LLM citation is different from traditional SEO:

- Checking with manual queries
- Brand monitoring tools
- The term: “Brand impression”: the number of times the brand appears in AI responses

**Tip:** Regularly test your important brand and product queries across at least 4-5 different LLMs. See which sources are shown for which questions; this becomes the roadmap for your content strategy.