Bing Index

The Bing index is Microsoft's database of crawled and processed web pages. It supplies results for Bing search and grounds Microsoft's AI products, including Microsoft Copilot and the AI-generated summaries in Bing. Outside Microsoft, OpenAI's help center lists Microsoft among the search providers that ChatGPT Search sends rewritten queries to, so a page's standing in Bing can affect whether it is retrieved for ChatGPT answers.

Pages enter the index when Bingbot crawls them, or faster when a site notifies Bing through IndexNow or submits URLs and sitemaps in Bing Webmaster Tools. Indexed pages are then available to every product that grounds on Bing. Developers reach the same index through Grounding with Bing Search in Microsoft's Azure AI Foundry, which replaced the standalone Bing Search APIs that Microsoft retired on August 11, 2025.

The link to AI search became directly measurable in 2026. On February 10, 2026 Microsoft released AI Performance in Bing Webmaster Tools as a public preview. According to the Bing Webmaster blog announcement, the report shows how often a site is cited in Microsoft Copilot, AI summaries in Bing and 'select partner integrations', with total citations, average cited pages per day, page-level citation counts and a sample of grounding queries, the phrases the AI used when it retrieved the cited content. Microsoft described it as 'an early step toward Generative Engine Optimization (GEO) tooling'. The data refreshes daily and can be exported, but it was not available through the Webmaster API at launch.

For GEO teams the Bing index matters for three reasons:

• Microsoft Copilot answers are grounded on it, so pages missing from Bing cannot be cited there.
• ChatGPT uses Microsoft as one of its search providers alongside OpenAI's own crawler and index, so Bing coverage helps ChatGPT retrieval without fully determining it.
• AI Performance is the first search-engine-owned report of AI citations and the grounding queries behind them, which is useful for checking third-party prompt tracking.

The basics are the same as for any index: make sure Bingbot can crawl and render key pages, keep XML sitemaps current, submit changes through IndexNow, and fix crawl errors in Webmaster Tools. Bing's own guidance in the AI Performance announcement adds clear headings, tables and FAQ sections, evidence for claims, and regular updates. For local businesses, Microsoft points to Bing Places so that address and hours data used in AI answers stays accurate. Promptwatch can pull Bing Webmaster data through its Bing Webmaster integration, so Bing citations and ChatGPT or Copilot citation share can be read side by side.