OpenAI is rolling out GPT-5.5 Instant as the new default model in ChatGPT, replacing GPT-5.3 Instant for all users. The update targets ChatGPT’s highest-volume everyday model, the one used by hundreds of millions of people for quick answers, writing help, analysis, coding support, image understanding, and general assistant tasks.
GPT-5.5 Instant is starting to roll out in ChatGPT.
— OpenAI (@OpenAI) May 5, 2026
It’s a big upgrade, giving you smarter, clearer, and more personalized answers in a warmer, more natural tone.
And it's also more concise, which we heard you wanted. We think you'll love chatting with it. pic.twitter.com/HSQOhjqxp7
The new Instant model is designed to produce clearer and shorter answers while raising accuracy across high-stakes and everyday prompts. OpenAI says GPT-5.5 Instant produced 52.5% fewer hallucinated claims than GPT-5.3 Instant on internal high-stakes evaluations covering medicine, law, and finance. It also reduced inaccurate claims by 37.3% on difficult conversations previously flagged by users for factual errors.
GPT-5.5 Instant brings stronger performance across visual reasoning, math, science, STEM questions, uploaded image analysis, and web-search decision-making. In practice, OpenAI positions the model as a faster daily assistant that can catch mistakes, recover from flawed reasoning, and return tighter answers with less unnecessary formatting.
GPT-5.5 Instant is starting to roll out to everyone in ChatGPT.
— ChatGPT (@ChatGPTapp) May 5, 2026
Much more concise. Better memory. More personalized.
And it's way easier to talk to. Really. pic.twitter.com/C6iCpFZte7
The update also pushes ChatGPT deeper into personalization. GPT-5.5 Instant can use context from past chats, uploaded files, and connected Gmail when available, helping users continue ongoing work or receive suggestions shaped by prior context. OpenAI is also introducing memory sources across ChatGPT models, giving users visibility into which memories or past chats were used for a personalized answer, with controls to delete or correct outdated context.
GPT-5.5 Instant begins rolling out today to all ChatGPT users and is also available in the API as chat-latest. Paid users will keep access to GPT-5.3 Instant for three months through model configuration settings before it is retired. Personalization from past chats, files, and connected Gmail is rolling out first to Plus and Pro users on the web, with mobile support coming soon and expansion planned for Free, Go, Business, and Enterprise users in the coming weeks. Memory sources are rolling out across ChatGPT consumer plans on the web first, with mobile support to follow.
OpenAI is using this launch to update the baseline ChatGPT experience rather than introduce a separate premium-only model. That makes GPT-5.5 Instant an important release for the company’s consumer product strategy, since improvements to the default model affect the largest share of ChatGPT usage. The move also shows OpenAI continuing to shift ChatGPT from a generic chatbot toward a more context-aware assistant that can draw on prior work, connected data, and user-controlled memory.
