GPT-5.5 Instant: smarter, clearer, and more personalized

Update on June 9, 2026: Personalization improvements are now rolling out to ChatGPT Go & Free. Responses on the Free tier will draw from a reduced set of past chats.

We’re updating ChatGPT’s default model, available to everyone, to be smarter and more accurate , with clearer, more concise answers that feel better tailored to you.

Because Instant is the daily driver for hundreds of millions of people, small improvements make a big difference. This update makes everyday interactions more useful and more enjoyable: stronger and tighter answers across subject areas, a more natural conversational tone, and better use of the context you’ve already shared when personalization can help.

Enhanced personalization from past chats, files, and connected Gmail is rolling out to Plus and Pro users on the web and coming soon to mobile with plans to expand to Free, Go, Business, and Enterprise in the coming weeks. Memory sources are rolling out across all ChatGPT consumer plans on the web and soon on mobile. Availability of specific personalization sources may vary by region.

Instant is now more dependable, with significant improvements in factuality across the board and the largest gains in domains where accuracy matters most. In internal evaluations, GPT‑5.5 Instant produced 52.5% fewer hallucinated claims than GPT‑5.3 Instant on high-stakes prompts covering areas like medicine, law, and finance. It also reduced inaccurate claims by 37.3% on especially challenging conversations users had flagged for factual errors.

GPT‑5.5 Instant is a generally smarter model that’s more capable across everyday tasks , including improvements in analyzing photo and image uploads, answering STEM-related questions, and deciding when to use web search to provide a more useful answer.

GPT‑5.5 Instant is the stronger answer because it recovers from its initial mistake: it first endorses the incorrect solution, but then catches that x =3 fails when plugged back into the original equation. It identifies the actual algebra error (the user moved terms incorrectly) and then uses the quadratic formula to get the correct solution. GPT‑5.3 Instant also catches that x =3 fails, but stops too early and incorrectly concludes there is no real solution instead of revisiting the algebra and solving the corrected quadratic.