GPT-5.5 Instant Rolls Out as Default ChatGPT Model
OpenAI is rolling GPT-5.5 Instant out over two days as the default model for all ChatGPT users. The release delivers significant factuality gains in medicine, law, and finance; better handling of image uploads, STEM tasks, and web search routing; and a "smarter, warmer, more concise" tone. Independent benchmark analysis by Ethan Mollick confirms an 86% GPQA score on the free tier — a level not reached by paid models until late 2025. A new Memory Sources feature lets ChatGPT draw on saved memories, past chats, connected Gmail, and uploaded files, with user-controlled visibility and deletion.
Why It Matters
GPT-5.5 Instant sets a new free-tier capability baseline and introduces deep personalization infrastructure that will shape competitive expectations across frontier AI products. Full launch details at OpenAI's announcement page.