How to Install and Run Codex CLI on Linux

Quick answer: install Codex CLI on Linux

# Official install script (no Node.js needed)
curl -fsSL https://chatgpt.com/codex/install.sh | sh

# Or with npm, if you already have Node.js
npm install -g @openai/codex

# Verify and start
codex --version
cd ~/my-project
codex

Codex is also available through Homebrew on Linux and as prebuilt binaries. Install options change from time to time, so check the official Codex CLI docs for the current list.

Requirements

• A 64-bit Linux on x64 or ARM64. Ubuntu, Debian and Fedora all work.
• Node.js only if you install through npm. The install script and the binaries do not need it.
• A ChatGPT plan that includes Codex, or an OpenAI API key.
• Git is strongly recommended: work inside a repository so every change Codex makes is easy to review and undo.

Signing in, including over SSH

The first time you run codex it asks how to sign in: with your ChatGPT account or with an API key. On a desktop, choosing ChatGPT opens the browser and returns to the terminal on its own.

On a server, a container or an SSH session, the browser callback cannot reach the CLI. Use device authentication instead:

codex login --device-auth

Open the link it prints on any device, sign in, and type the one-time code. Some ChatGPT workspaces must enable device code login in their security settings first. If it is not available, the authentication docs list the fallbacks.

What about the ChatGPT desktop app on Linux?

OpenAI has released its ChatGPT desktop app for Linux as a preview, and it includes Codex. It targets Ubuntu, Debian and Fedora on x64 and ARM64, and some features, such as Computer Use, are not available on Linux yet. If you want OpenAI's own app, it is worth a try.

CodeAgentSwarm is not a replacement for it. It is built around the Codex CLI you just installed: several Codex terminals at once, next to Claude Code and other agents if you use them, with one place to see which agent is done and what each one changed.

Common Linux errors and how to fix them

• "codex: command not found": the install folder is not on your PATH yet. Open a new terminal first. With npm, run npm prefix -g and make sure its bin folder is on your PATH.
• EACCES errors with npm install -g: do not use sudo. Install Node.js with nvm, or point npm at a folder you own with npm config set prefix ~/.npm-global and add ~/.npm-global/bin to your PATH. Or skip npm and use the install script.
• Login hangs on a remote machine: the browser callback cannot reach the server. Use codex login --device-auth.
• Wrong account or expired session: run codex logout, then codex login again.

Running several Codex sessions on Linux

Once Codex works, one terminal quickly feels slow: you give it a task and wait. More tabs or a tmux layout help, until you forget which session finished, which one is waiting for an approval and what each one touched.

CodeAgentSwarm is a desktop app for running several agent terminals at once, and it now runs on Linux as a .deb (Ubuntu, Debian and derivatives) or an AppImage (Fedora and most other distros), for x64 and ARM64. You pick Codex in each terminal and get desktop notifications when an agent finishes or needs input, searchable history across sessions and a live diff per terminal.

Next steps: running a Codex agent swarm and running multiple Codex sessions. Want Claude Code on the same machine? See Claude Code on Linux.

Conclusion

Codex CLI on Linux is one script or one npm install away. Sign in with ChatGPT on a desktop or with device auth on a server, work inside a git repository, and when one terminal is not enough, run several side by side in CodeAgentSwarm.