ChatGPT is a free-to-use AI system. Free GPT online. No login required. Use it for engaging conversations, gain insights, automate tasks, and more, all in one place. OpenAI’s GPT-o4-mini-high is one of the latest AI models shaking up the ChatGPT ecosystem. Introduced in April 2025 as part of OpenAI’s new “o-series” reasoning models, GPT-o4-mini-high is designed to “think longer” and tackle complex tasks with advanced reasoning. Do more on your PC with ChatGPT: · Instant answers—Use the [Alt + Space] keyboard shortcut for faster access to ChatGPT · Chat with your computer—Use Advanced Voice to chat with your computer in real-time and get hands-free advice and answers while you work. Chat with ChatGPT for free online. No registration required. Powered by OpenAI GPT-4o. Log in or sign up to ChatGPT Continue with Google Continue with Apple Continue with phone OR Continue Try it first ChatGPT Terms of use Privacy policy We’ve trained a model called ChatGPT which interacts in a conversational way. The dialogue format makes it possible for ChatGPT to answer followup questions, admit its mistakes, challenge incorrect premises, and reject inappropriate requests. ChatGPT is a generative artificial intelligence chatbot developed by OpenAI. Originally released in November 2022, the product uses large language models —specifically generative pre-trained transformers (GPTs)—to generate text, speech, and images in response to user prompts.