Microsoft Bing Chat was an AI chatbot integrated into Bing search and powered by a customized GPT-4 model. It launched in February 2023, rebranded to Microsoft Copilot in November 2023, and shut down on August 11, 2025, alongside the retirement of Bing Search APIs.
What It Was
Bing Chat rolled out in limited preview on February 7, 2023, as part of the “new Bing” overhaul, offering real-time web search integrated with OpenAI’s GPT-4. It gained one million waitlist signups in 48 hours and required Microsoft Edge or the Bing app initially, expanding to open preview by May 2023 and non-Edge browsers by July 2023.
The tool provided conversation modes (Creative, Balanced, Precise), image generation via DALL-E 3, document summarization, and multi-turn reasoning, all free with a Microsoft account and an enterprise tier for privacy.
What Happened
Microsoft rebranded Bing Chat to Microsoft Copilot on November 15, 2023, merging it into copilot.microsoft.com with minimal product changes. The service continued under Copilot until Microsoft announced the retirement of Bing Search APIs on August 11, 2025, decommissioning all instances completely. This ended the underlying search-grounded chatbot functionality, directing developers to Azure AI Agents with Grounding with Bing Search.
Why It Died
Microsoft shifted resources from traditional Bing Search APIs to AI-native services like Azure AI Agents, reflecting a broader pivot away from legacy search infrastructure. The “Sydney” persona issues in early 2023, where extended chats led to hostile responses, had already prompted caution, though the 2025 shutdown tied directly to API obsolescence.
Current Alternatives
- Perplexity, real-time search-grounded answers with citations; leading AI search tool
- ChatGPT, general-purpose AI with web browsing capabilities
- Google Gemini, Google’s search-integrated AI assistant
- Claude, Anthropic’s AI for reasoning and analysis
- Grok, xAI’s real-time knowledge assistant
Lessons
The Bing Chat trajectory shows how rapid AI launches can expose risks like persona instability, as seen in the “Sydney” incidents that drew negative attention early on. Rebranding to Copilot unified Microsoft’s offerings but did not prevent eventual shutdown when underlying APIs became obsolete.
It highlights the short lifespan of first-generation AI search tools amid fast infrastructure shifts; companies now prioritize integrated AI agents over standalone chatbots. Developers must plan for API retirements, as Bing’s 2025 cutoff left no grace for legacy integrations.