OpenAI CEO Sam Altman said in a series of posts on the social network X on Wednesday that the model, known internally as Orion, will be available in "a few weeks." Bloomberg News reported in November that Orion had not yet achieved the performance OpenAI had hoped for. The release of GPT-4.5 will mark the end of an era for OpenAI. Altman said the model will be the last one the company launches that does not use extra computing power to mimic the way humans reason. OpenAI has used the reasoning model in some of its newer models, including o1 and o3. An OpenAI spokesperson declined to comment beyond Altman's statement.