OpenAI Codex

What Is OpenAI Codex?

Codex is OpenAI's coding agent. It can finish engineering tasks such as building features, refactoring code and running migrations. Developers can use it in the Codex app, an IDE extension, a command-line tool or cloud environments. Agents can work in parallel, and a review panel shows the files they changed. Codex is included in ChatGPT plans.

Who Should Use OpenAI Codex?

Codex is useful for software developers and engineering teams who want an AI agent to handle coding tasks. Teams with repeated work can use Skills and Automations. Buyers should check the usage limits, because the screenshot lists Free and Go for testing Codex and shows no numbers for any plan.

How Does OpenAI Codex Work?

1. Sign in with your ChatGPT account and pick a place to use Codex: the Codex app, an IDE extension or the CLI.
2. Give Codex a coding task, such as a new feature, a refactor or a migration.
3. Let agents work in parallel using worktrees and cloud environments, and follow their progress.
4. Check the files that changed in the review panel.
5. Add Skills for your team's standards, or set up Automations for scheduled background work.

OpenAI Codex Pricing and Plans

The screenshot shows the Individual view with four plans: Free, Go, Plus and Pro. A line at the top says Codex is included in ChatGPT Free, Go, Plus, Pro, Business and Enterprise plans. The price numbers do not show in the screenshot, so this overview lists no prices. Free and Go are for testing Codex. Plus adds expanded Codex usage and the Codex app for macOS and Windows. Pro adds maximum Codex tasks. The Business and Enterprise tab is not shown.

Official pricing page: https://openai.com/codex/

Is OpenAI Codex Free?

Yes, with limits. The screenshot shows a Free plan with Test Codex Capabilities, limited access to the flagship model GPT-5.6, and limited messages, uploads, image generation, deep research, memory and context. The price does not show in the screenshot, and it gives no numbers for the limits.

OpenAI Codex Key Features

Codex App

The Codex app is a command center where several agents work in parallel across projects. It uses built-in worktrees and cloud environments, tracks progress and shows a review panel for changed files. The Plus plan in the screenshot lists the Codex app for macOS and Windows.

IDE Extension and CLI

Codex also works inside a code editor through an IDE extension and in a terminal through the CLI. All surfaces connect through the same ChatGPT account, so users can use one agent across ChatGPT, their editor and the terminal. The pages do not list exact editors or systems.

Code Review

Codex reviews pull requests and aims to catch issues early. Developers can read the changes in the review panel before they accept them. This helps teams that want a second check on code that agents or people write. The homepage does not list supported code hosts.

Skills and Automations

Skills let users teach Codex their team's standards and workflows so it applies them across tasks. Automations let Codex run scheduled background work, such as issue triage, alert monitoring and CI/CD tasks. These help teams that repeat the same steps often.

Plugins and Plan Extras

On the Plus plan, the screenshot lists Plugins that connect tools such as Slack, GitHub and Figma. Plus also lists advanced reasoning models, expanded deep research and agent mode, and projects, tasks and custom GPTs. Pro adds maximum Codex tasks and Pro reasoning.

Should You Use OpenAI Codex?

Codex fits developers who already use ChatGPT and want a coding agent in an app, an editor or a terminal. The Free and Go plans let users test it, while Plus and Pro raise Codex usage. The screenshot shows no prices or usage numbers, so check them on the live page before buying. This overview is based on publicly available product information and is not a hands-on review.