The best way to build with agents. Codex accelerates real engineering work, from planning and building features to refactors, reviews, and releases—working seamlessly across your tools.
Codex CLI is OpenAI’s coding agent that you can run locally from your terminal. It can read, change, and run code on your machine in the selected directory. It’s open source and built in Rust for speed and efficiency. ChatGPT Plus, Pro, Business, Edu, and Enterprise plans include Codex. Learn more about what’s included.
The Codex app is a focused desktop experience for working on Codex threads in parallel, with built-in worktree support, automations, and Git functionality. ChatGPT Plus, Pro, Business, Edu, and Enterprise plans include Codex. Learn more about what’s included.
Codex can perform tasks for you such as writing features, answering questions about your codebase, fixing bugs, and proposing pull requests for review; each task runs in its own cloud sandbox environment, preloaded with your repository. Codex is powered by codex-1, a version of OpenAI o3 optimized for software engineering.
Codex is included in your ChatGPT Free, Go, Plus, Pro, Business, Edu, or Enterprise plan
The updated Codex app for macOS and Windows adds computer use, in-app browsing, image generation, memory, and plugins to accelerate developer workflows.
Codex One agent for everywhere you code Codex is OpenAI’s coding agent for software development. ChatGPT Plus, Pro, Business, Edu, and Enterprise plans include Codex. It can help you: Write code: Describe what you want to build, and Codex generates code that matches your intent, adapting to your existing project structure and conventions.
OpenAI Codex is a descendant of GPT‑3; its training data contains both natural language and billions of lines of source code from publicly available sources, including code in public GitHub repositories.