Last night, OpenAI announced GPT‑5.3 Instant, the successor to ChatGPT’s most-used model, GPT‑5.2 Instant. OpenAI claimed that this new model will deliver more accurate answers with richer and better-contextualized results from the web. Instead of targeting AI benchmarks, OpenAI focused on improving tone, relevance, and conversational flow.
The GPT‑5.3 Instant model is now available for all ChatGPT users, replacing GPT-5.2. However, paid users can still access GPT‑5.2 Instant for three months in the model picker under the Legacy Models section.
Microsoft has announced that the GPT‑5.3 Instant model is now available to Microsoft 365 Copilot and Copilot Studio users. In Microsoft 365 Copilot Chat, this new model appears as "GPT‑5.3 Quick response" in the model selector, and in Copilot Studio as "GPT‑5.3 Chat." Microsoft mentioned that paid Microsoft 365 Copilot users will have priority access to this new model, while free users will have standard access.
Microsoft also announced that the GPT-5.3 Instant model is coming to Microsoft Foundry via an API, allowing developers and enterprises to build AI applications. Microsoft highlighted that this new model comes with the following improvements, making it more suitable for enterprise scenarios:
- Proportionate Safety: Cut down on dead ends with fewer unnecessary refusals and more proportionate, safe responses.
- Adaptive Guidance: When a request needs a tweak, it reformulates compliantly and keeps the conversation moving.
- Grounded Resolution: Built-in web search plus model reasoning delivers grounded, operational answers, not long, loosely related link lists. That means end-to-end resolution for support, IT, and policy workflows, with enterprise controls and traceability intact.
- Reliable Performance: At scale, you get more consistent outputs: better tone, clearer explanations, stronger instruction following, and less cleanup.
OpenAI also confirmed that updates to Thinking and Pro models are coming soon. These updated models will also be made available on Microsoft"s products and services, including Copilot and Microsoft 365 Copilot.