# ChatGPT Search is (mostly) the Bing index — BWT is a prerequisite

**Confidence: [H]** (multiple overlap studies)

Seer (2026-04): **87% of ChatGPT citations match Bing top-10** (vs 56%
Google top-10); earlier studies ~73%. ChatGPT Search = Bing index + its own
OAI-SearchBot crawl + internal `web.run` fan-out queries.

**How to apply:** for ChatGPT visibility, Bing indexing is table stakes —
register Bing Webmaster Tools, submit sitemaps, fix Bing-side crawl issues,
and check Bing rankings for priority queries. Bing Places matters for local
([[local-ai-gap]]). Don't block Bingbot ([[bot-taxonomy-three-classes]]).

**Evidence:** https://www.soci.ai/blog/how-to-rank-in-chatgpt-perplexity-and-google-ai-overview/ ·
https://searchengineland.com/inside-chatgpt-search-web-run-fan-out-queries-ai-visibility-477339
