Codex: How to install Codex in Linux?

To install OpenAI Codex CLI on Linux, use the npm method. The official Codex docs say the CLI supports Linux, can be installed with npm, and starts with the codex command. The first run prompts you to sign in with your ChatGPT account or an API key. (OpenAI Developers)

1. Install Node.js and npm

For Ubuntu/Debian:

sudo apt update
sudo apt install -y nodejs npm git

Check:

node -v
npm -v

2. Install Codex CLI

sudo npm i -g @openai/codex

Official install command:

npm i -g @openai/codex

I used sudo above because many Linux systems require admin permission for global npm installs.

3. Run Codex

Go to your project folder:

cd /path/to/your/project

Start Codex:

codex

On first run, it will ask you to sign in using your ChatGPT account or an OpenAI API key. (OpenAI Developers)

4. Upgrade later

sudo npm i -g @openai/codex@latest

That is the official upgrade command for npm installs. (OpenAI Developers)

Common errors

If you get:

codex: command not found

Try:

npm bin -g

Then make sure that global npm path is in your PATH.

If install fails with permission errors, use:

sudo npm i -g @openai/codex

or install Node through a user-level Node manager and then run npm without sudo.

Important note

On Linux, use Codex CLI. The official Codex desktop app is currently listed for macOS and Windows, while the CLI is the Linux-supported option. (OpenAI Developers)