GPT-4o mini is OpenAI’s small multimodal model, released July 18, 2024, as a cheaper replacement for GPT-3.5 Turbo in the API and free tier of ChatGPT. It takes text and image input, holds a 128K token context window, and costs 15 cents per million input tokens and 60 cents per million output tokens, a fraction of what the full GPT-4o charges. Despite the small footprint, it scored 82.0 on MMLU and 87.2 on HumanEval at launch, beating comparable small models from Google and Anthropic on most published benchmarks at the time. OpenAI positioned it for high-volume tasks like customer support, content moderation, and simple coding assistance where GPT-4o-level reasoning is not worth the extra cost. It has since been layered under successive OpenAI releases, but its price point kept it in wide use among developers building cost-sensitive applications.