OpenAI Launches GPT-5.5 Instant With 52% Fewer Hallucinations and New Memory Controls Across All ChatGPT Models
Summary
OpenAI launches GPT-5.5 Instant with 52% fewer hallucinations, replacing GPT-5.3 Instant as ChatGPT's default model while rolling out new memory controls across all ChatGPT models for greater user transparency and personalization.
Key Points
- OpenAI launches GPT-5.5 Instant, replacing GPT-5.3 Instant as the default ChatGPT model, boasting significant factuality improvements including 52.5% fewer hallucinations on high-stakes prompts and 37.3% fewer inaccurate claims on flagged conversations.
- The upgraded model delivers enhanced capabilities across multimodal reasoning, STEM questions, document parsing, tighter responses, and improved personalization using past chats, connected files, and Gmail — with expanded rollout coming to more plans in the coming weeks.
- OpenAI also introduces memory sources across all ChatGPT models, giving users greater transparency and control over how their past conversations are referenced and used to personalize responses, rolling out now on web with mobile support coming soon.