OpenAI Launches GPT-5.5 Instant as New Default Model for ChatGPT
OpenAI officially launches GPT-5.5 Instant, replacing GPT-5.3 Instant as the default model for ChatGPT. The model emphasizes greater accuracy, conciseness, and understanding of the user: hallucination rates in medical, legal, and financial domains have decreased by 52.5%, and math competition scores have significantly improved; responses are shorter and more natural, reducing excessive formatting. Plus/Pro users can access historical conversations and files for personalized answers, and all consumer versions will feature a new "Memory Source" function for users to view and manage.
OpenAI officially launches GPT-5.5 Instant, replacing GPT-5.3 Instant as the default model for ChatGPT. The model emphasizes greater accuracy, conciseness, and understanding of the user: hallucination rates in medical, legal, and financial domains have decreased by 52.5%, and math competition scores have significantly improved; responses are shorter and more natural, reducing excessive formatting. Plus/Pro users can access historical conversations and files for personalized answers, and all consumer versions will feature a new "Memory Source" function for users to view and manage.
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