Bing and Copilot

StatCounter puts Bing at 4.5% worldwide in August 2026, second to Google's 91.1%^[2], and at 8.92% in the United States against Google's 86.1%^[6]. The syndication footprint is larger than the share suggests: Yahoo Search has run on Bing since the July 2009 partnership^[3], and DuckDuckGo and Ecosia also draw results from it. Bing reported 100 million active users in March 2023 after an OpenAI-based chatbot was added to search^[7].

Microsoft made Bing the default search engine for ChatGPT Plus users in May 2023^[4], and when OpenAI shipped a dedicated ChatGPT search product on 31 October 2024^[8], GeekWire noted that OpenAI had partnered with Bing for web search results in the past^[9]. By mid-2026 the dependency looks broken: a Search Engine Land teardown reports OpenAI running its own web index, with only 1.5% of its result URLs appearing in Bing's top 20 for the same fan-outs^[10]. The field that let outside researchers see which index answered a given query disappeared from the retrieval stream overnight on 21 July 2026^[11]. Both findings rest on one publication's instrumentation, so treat the split as reported rather than settled.

Microsoft reported more than 20 million paid Microsoft 365 Copilot seats at its April 2026 earnings call, with weekly engagement at the level of Outlook^[12], and more than 30 million paid seats by July 2026 alongside 50 million GitHub Copilot users^[13]. Those are licence counts, not queries, and they cover the workplace assistant rather than the consumer answer surface, so they set an upper bound on reach rather than measuring it.

Access to publisher content is not what limits Copilot's answers. In the Columbia Journalism Review's audit of eight AI search tools, Copilot was the only one no publisher in the sample blocked, and it still declined to answer more often than any of the other seven^[14]. See citation accuracy.

Microsoft ties bingbot's user-agent strings to the current stable version of the Edge rendering engine, so the strings change as Edge does^[15]. Anything matching a fixed string in robots.txt or a log filter therefore ages out. IndexNow, the push protocol Microsoft introduced with Yandex, lets a site tell participating engines the moment a page changes instead of waiting for a recrawl^[5]. Adoption grew to about 2.5 billion submitted URLs by 2024, and Bing reports 17% of all clicked URLs on the engine arriving through it^[16]. As of 2022 Google had not officially adopted it, relying on its own Indexing API for content like job postings^[17].