ChatGPT uses Bing. Gemini uses Google. Claude uses Brave. Perplexity uses its own. Tracking AI visibility means tracking four indexes, not one.

AI Citations: how ChatGPT, Claude, Gemini, Perplexity choose what to cite

ChatGPT uses Bing. Gemini uses Google. Claude uses Brave. Perplexity uses its own. Tracking AI visibility means tracking four indexes, not one.