Microsoft Bing

By Bill Hartzer · Updated 19 August 2026

Bing has its own index, and that is the most important fact about it

Microsoft Bing crawls the open web with its own crawler and ranks its own index — the engine's own stored copy of the web. It takes web-link results from no other general search engine. That deserves stating flatly and up front, because the most common error made about Bing is to file it as a second-tier reseller sitting downstream of somebody else's work. It is the opposite. Bing is one of only two large independent indexes of the open web in the Western market, and the other one is Google's.

The consequence runs through the whole search landscape. Yahoo's web results have come from Bing since the 2009 search alliance. DuckDuckGo's web links come substantially from Bing. Ecosia and Qwant have drawn on Bing at various points. When people talk about “alternative search engines,” a large share of what they are actually using is Bing's crawl with a different interface, a different privacy policy and a different business model wrapped around it.

This makes Bing structurally important out of all proportion to its own market share. A crawling decision, a licensing decision or a pricing decision made in Redmond propagates to a dozen consumer brands that most users assume are independent. Anyone trying to understand who actually indexes the web needs to count Bing as one of the small number of organisations that does.

How it gets its results: bingbot, IndexNow, and the index

The crawler is bingbot. Microsoft publishes its user-agent strings — the identifying text a crawler sends with each request — in desktop and mobile variants, both containing compatible; bingbot/2.0, with a robots.txt token of bingbot. The current strings date from an April 2022 announcement; the older format was retired in autumn 2022. Microsoft also documents adidxbot, which verifies advertisers' landing pages, and MicrosoftPreview, which renders page snapshots.

Microsoft has additionally introduced user agents connected to AI training and answers, but the precise current list could not be verified from Microsoft's own documentation, so this page does not enumerate them.

Alongside conventional crawling, Bing co-created IndexNow, an open push-submission protocol launched in October 2021 jointly with Yandex. Instead of waiting for a crawler to revisit, a site notifies participating engines that a URL has changed and they fetch it. It is a genuinely useful open standard, and it is unusual for being cross-vendor rather than proprietary.

One structural change matters more than any of the technical detail. On 11 August 2025 Microsoft retired all Bing Search APIs, decommissioning existing instances, closing new signups, and directing customers to Grounding with Bing Search inside Azure AI Agents. That replacement is a product for grounding large language models, not a raw results feed. Independent engines, research tools and applications that resold Bing results through the public API lost that route entirely. Any claim after August 2025 that some engine “uses Bing” should prompt the question: under what contract? A direct syndication agreement and a retired public API are very different things.

Who runs it, how it makes money, and how it got here

Bing is Microsoft's, and always has been. Bing itself was announced by Steve Ballmer on 28 May 2009 and launched on 3 June 2009; since the 2024 reorganisation it has sat within the Microsoft AI organisation under Mustafa Suleyman.

Revenue comes from advertising, sold through Microsoft Advertising on an auction basis across paid search, shopping and audience formats, both directly and through the Microsoft Search Network, which includes Yahoo and other syndication partners. Microsoft reports the result within its “Search and news advertising” line. Two secondary flows are worth understanding structurally: Microsoft pays syndication partners such as Yahoo and DuckDuckGo a share of ad revenue for the traffic they send, and Azure now meters Grounding with Bing Search as a cloud service. Microsoft Rewards, which pays users points for searching, is a customer-acquisition cost rather than a revenue source. Bing is free to users.

The predecessor brands were Microsoft's too. MSN Search launched in 1998 using third-party results — Inktomi first, later LookSmart and AltaVista. Microsoft began building and using its own crawler and index around 2004 to 2005, the point at which it became an independent engine rather than a front end. Windows Live Search replaced MSN Search on 11 September 2006 and was renamed Live Search on 21 March 2007.

The defining commercial event came weeks after Bing's launch. On 29 July 2009 the ten-year Microsoft–Yahoo Search Alliance was announced: Bing would power Yahoo's web results, with Yahoo taking 88% of search advertising revenue on its own sites for the first five years. The transition completed in the US in October 2011 and migration finished by early 2012. In April 2015 the deal was renegotiated on materially looser terms — Bing was required on only the “majority” of Yahoo desktop search traffic, Yahoo was freed on mobile, and either party could terminate on four months' notice.

Since then: IndexNow with Yandex in October 2021, the CNIL fine in December 2022, GPT-4 Bing Chat in February 2023, the Copilot rebrand in November 2023, sharp Bing Search API price rises announced in 2023 that squeezed downstream engines, and the full API retirement in August 2025.

Privacy, censorship and regulation

Bing is a mainstream, advertising-funded engine owned by a company with an unusually large consumer and enterprise data estate: Windows, Edge, LinkedIn and Microsoft 365. Search performed while signed in to a Microsoft account is linked to that account. It is not a privacy-focused engine and does not present itself as one.

Microsoft's privacy statement describes de-identification applied to stored queries over time, and Microsoft has historically stated that it removes the full IP address after a period and other identifiers later still. Those durations have been restated over the years and are not reproduced here as current fact; the privacy statement itself is the authority. Users can view and clear search history in their Microsoft account privacy dashboard.

Two matters of independent scrutiny belong on the record. In December 2022 France's data protection regulator, the CNIL, fined Microsoft Ireland €60m over cookies dropped on bing.com without consent — among the largest cookie fines issued. And Bing has a documented censorship problem. It operates a filtered version in mainland China, and Citizen Lab research published in 2022 by Jeffrey Knockel found that Bing's autosuggestion system censored politically sensitive Chinese names for North American users as well as Chinese ones. Political filtering that leaks outside the jurisdiction requiring it is not a minor complaint about a reference tool.

On regulation, a widely repeated claim needs correcting: Bing is not a designated core platform service under the EU Digital Markets Act. Checked against the European Commission's gatekeeper register on 19 August 2026, Microsoft's designated core platform services are LinkedIn and Windows PC OS only. Google Search is designated (Case DMA.100004). The practical effect is that Bing carries none of the DMA obligations on self-preferencing, choice screens and data use that its main rival does.

AI: Bing got there first, and it did not change the share

On 7 February 2023 Microsoft launched “the new Bing” with an integrated GPT-4-based chatbot, Bing Chat — the first mainstream integration of a large language model into a web search engine, ahead of Google. In March 2023 Microsoft said Bing had passed 100 million daily active users; that figure is from March 2023 and should not be read as current, since Microsoft has not published an auditable usage number since.

The early failure mode is worth recording rather than quietly forgetting. In February 2023 Bing Chat produced widely reported erratic, argumentative and hallucinated output — the “Sydney” persona — and Microsoft responded by capping conversation turns.

On 15 November 2023 Bing Chat was rebranded to Microsoft Copilot and progressively separated into a standalone product at copilot.microsoft.com while remaining embedded in the Bing results page. Through 2024 to 2026 Bing has served AI-generated summaries above conventional results for many queries. The models are primarily OpenAI's, supplemented by Microsoft's own MAI models announced in 2025; Microsoft does not publish a per-surface model map, so the exact current mix is not stated here. No documented setting fully disables AI answers on bing.com.

The honest conclusion from three years of this: Bing's own market share stayed roughly flat despite the AI investment. Being first with a chatbot in search did not move the needle the way Microsoft publicly hoped in 2023.

Market share: quote the right number

All figures below are StatCounter Global Stats for July 2026, accessed 19 August 2026. StatCounter measures tracked page views rather than users or queries, so it is a standard public proxy, not a census.

Worldwide, all devices: 4.47% (Google 91.31%)
Worldwide, desktop only: 8.84% (Google 86.12%)
United States, all devices: 8.63% (Google 86.6%)

The desktop/mobile split is the single most important nuance about Bing's position. Bing is materially stronger on desktop because it is the default in Windows and Edge, and very weak on mobile, where it has no default placement. Quoting the worldwide all-device figure alone understates Bing in exactly the market that matters most to advertisers. Both numbers are true; a writer citing one without the other is telling half the story.

What it is good at, and what it is bad at

Good at: being genuinely independent, which is the whole ballgame — it is the reason a non-Google search ecosystem exists. Bing is strong on desktop, well integrated with Windows and Edge, good at image and video search, and generous with free webmaster tooling. IndexNow is a real contribution to open infrastructure. Microsoft Advertising is cheaper per click than Google Ads in most verticals.

Bad at: long tail and freshness. Bing's index is smaller than Google's and it is noticeably weaker on obscure queries, very recent pages and non-English long-tail material. Local search outside major markets is weaker. The results page is heavy with Microsoft-owned modules and Rewards prompts. And the censorship finding is unresolved: documented political filtering that reached users outside China is a serious problem for anything used as a reference tool.

Who should not use it: anyone whose work depends on finding rare or very recent pages; anyone researching topics censored by the Chinese state, where Bing's autosuggest and results have been shown to be filtered; anyone wanting a privacy-preserving engine. Developers needing a raw web-search API should also look elsewhere — that door closed on 11 August 2025.

Common misconceptions

“Bing is a Yahoo skin.” Backwards. Bing powers Yahoo, not the other way round, and has since the 2009 alliance.
“Bing doesn't have its own index; it copies Google.” False. Bing crawls independently. The 2011 episode that produced this belief concerned Bing using anonymised Internet Explorer and Bing Toolbar clickstream data as one ranking signal, which caused Google's results for synthetic nonsense queries to surface in Bing during a Google sting. That was a clickstream signal, not index copying.
“Bing's share is about 3%.” That is the worldwide all-device figure. Worldwide desktop is around 8.8% and the US around 8.6% (StatCounter, July 2026). Cite the one that fits the question.
“You can get Bing results through the Bing Search API.” Not since 11 August 2025.
“Copilot is Bing.” Copilot is now a separate Microsoft product line. Bing embeds it; they are not the same thing.
“Bing was designated a gatekeeper under the DMA.” It was not. Per the Commission's register, Microsoft's designated core platform services are LinkedIn and Windows PC OS.

Frequently asked questions

Does Bing have its own search index?

Yes, emphatically. Microsoft crawls the open web with its own crawler, bingbot, and ranks its own index. Bing takes web-link results from no other general search engine, and it is one of only two large independent indexes of the open web in the Western market. It is also the wholesale supplier behind Yahoo, DuckDuckGo and, at various times, Ecosia and Qwant.

Which search engines use Bing's results?

Yahoo Search has taken its web results from Bing since the 2009 Microsoft–Yahoo Search Alliance, and DuckDuckGo sources web links substantially from Bing. Ecosia and Qwant have used Bing at various points. Because so much of the visible “alternative search” market is Bing's crawl behind a different interface, Microsoft's crawling and licensing decisions propagate widely across engines users assume are independent.

Is the Bing Search API still available?

No. Microsoft retired all Bing Search APIs on 11 August 2025, decommissioning existing instances and closing new signups. The stated replacement is Grounding with Bing Search inside Azure AI Agents, which is a product for grounding large language models rather than a raw results feed. Tools and engines that resold Bing results through the public API lost that route entirely.

What is Bing's market share?

StatCounter Global Stats for July 2026 put Bing at 4.47% worldwide across all devices, 8.84% on desktop worldwide, and 8.63% in the United States across all devices. The gap is the point: Bing is strong on desktop, where it is the Windows and Edge default, and weak on mobile, where it has no default placement. StatCounter measures tracked page views, not users or queries.

Does Bing copy Google's results?

No. Bing crawls the web itself with bingbot and ranks its own index. The belief comes from a 2011 episode in which Google ran a sting using synthetic nonsense queries and found them surfacing in Bing. The cause was Bing's use of anonymised Internet Explorer and Bing Toolbar clickstream data as one ranking signal among many, not copying of Google's index.

Is Bing private?

No, and it does not claim to be. Bing is advertising-funded and owned by a company with a very large data estate spanning Windows, Edge, LinkedIn and Microsoft 365; search performed while signed in is linked to a Microsoft account. Microsoft describes de-identification of stored queries over time and offers a privacy dashboard for viewing and clearing history, but the posture is mainstream commercial, not privacy-preserving.

Does Bing censor results?

Bing operates a filtered version in mainland China, and Citizen Lab research published in 2022 by Jeffrey Knockel found that Bing's autosuggestion system censored politically sensitive Chinese names for North American users as well as Chinese ones. Censorship that leaks beyond the jurisdiction requiring it is a real limitation for anyone researching topics the Chinese state restricts, and it remains the most serious credibility issue attached to the engine.

Is Bing a gatekeeper under the EU Digital Markets Act?

No. Checked against the European Commission's gatekeeper register on 19 August 2026, Microsoft's designated core platform services are LinkedIn and Windows PC OS; Bing is not designated. Google Search is designated as Case DMA.100004. In practice Bing carries none of the DMA obligations on self-preferencing, choice screens and data use that apply to Google Search in the EU.