What is OpenAI Codex?
Codex is OpenAI's software engineering agent, available in ChatGPT, as an open-source CLI and as an IDE extension. It can work on tasks in parallel cloud sandboxes, answer questions about a codebase and propose pull requests.
Best for: Developers using ChatGPT, Engineering teams.
Key features
- Cloud task sandboxes
- Codex CLI
- IDE extension
- GitHub PR creation
- Code review
Pros and cons
Pros
- Included with ChatGPT paid plans
- Runs many tasks in parallel
- Open-source CLI
Cons
- Cloud tasks can be slow for small edits
- Best features need higher ChatGPT tiers
OpenAI Codex pricing
| Pricing model | Paid |
|---|---|
| Starting price | $20/mo |
| Platforms | Web, Mac, Linux, Windows, VS Code |
| Launched | 2025 |
Prices change often. Check the OpenAI Codex website for current plans.
Our verdict
OpenAI Codex scores 9.0/10 in our review. Its biggest strength: included with ChatGPT paid plans. The main drawback: cloud tasks can be slow for small edits. If it isn't the right fit, ChatGPT is the closest alternative.
OpenAI Codex compared
Frequently asked questions
What is OpenAI Codex?
Codex is OpenAI's software engineering agent, available in ChatGPT, as an open-source CLI and as an IDE extension. It can work on tasks in parallel cloud sandboxes, answer questions about a codebase and propose pull requests.
Is OpenAI Codex free?
No. OpenAI Codex is a paid tool starting at $20/mo.
What are the best OpenAI Codex alternatives?
Popular alternatives include ChatGPT, GitHub Copilot, Cursor, Claude Code.
Who is OpenAI Codex best for?
OpenAI Codex is best for developers using chatgpt, engineering teams.