OpenAI releases GPT-5.5 Instant, a new default model for ChatGPT
TechCrunch
OpenAI has launched GPT-5.5 Instant as the new default ChatGPT model, offering improved reasoning, lower hallucinations, and enhanced memory source management.Summary
OpenAI has introduced GPT-5.5 Instant, replacing GPT-5.3 Instant as the default model for ChatGPT. The new version offers significant performance improvements, including higher scores on AIME 2025 and MMMU-Pro benchmarks, alongside reduced hallucination rates in specialized fields like law and medicine. A key feature is enhanced context management, allowing the model to pull information from past chats, files, and Gmail, with new transparency tools that let users track and manage memory sources. While the model is currently rolling out to Plus and Pro users on the web, developers can access it via API under the 'chat-latest' designation.
(Source：TechCrunch)