OpenAI's release of GPT-5 included embedding the new AI model into its AI chatbot to produce ChatGPT 5. But ChatGPT 5 isn't a singular model; there are three variations, Fast, Thinking, and Pro. You can choose any of them as the source of responses to your prompts, or let the AI automatically decide for you based on what you submitted.
And while they share the same LLM DNA, each model has its own approach to answering requests, as evidenced by their names. Fast is built for speed, answering the quickest and prizing efficiency over nuance. The Thinking model takes longer and goes for depth. You can follow along with its logical steps for the minute or two it takes to answer, offering more structure and context than Fast.
