OpenAI said it is releasing GPT-4o mini, a cheaper and smaller version of its most powerful AI model GPT-4o. The mini model outperforms the GPT-4 model on chat preferences and scored 82% on Massive Multitask Language Understanding (MMLU), OpenAI said. GPT-4o mini is more than 60% cheaper than GPT-3.5 Turbo, the startup added.