Product line slimming, OpenAI will retire classic inference models OpenAI o3 and GPT-4.5 from ChatGPT According to Beating monitoring, OpenAI announced in the latest ChatGPT release notes that in order to further optimize resource allocation, OpenAI O3 and GPT-4.5 models will be retired from the ChatGPT webpage and mobile interface. This move aims to clean up the low usage of the old models, thereby concentrating more computing resources and engineering efforts on the latest and more powerful GPT-5.5 flagship series (including GPT-5.5 Instant, GPT-5.5 Thinking, and GPT-5.5 Pro). The specific retirement schedule is as follows: GPT-4.5: entering a 30 day transition period, scheduled to officially go offline on June 27, 2026; OpenAI O3: Enters a 90 day transition period and is scheduled to officially go offline on August 26, 2026. Before their respective offline deadlines, ChatGPT paying users can still manually choose to use them in the model settings. In addition, OpenAI's API services are temporarily not affected by this adjustment, and developers can still continue to call OpenAI O3 and GPT-4.5 models through the API. [Original link]