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OpenAI

OpenAI Codex

A coding agent included with ChatGPT plans

Free plan Korean supported

Last verified:

Open official site (opens in a new tab)

Key specs

OpenAI Codex key specs
Price Free plan
Free limits Available with strict limits on Free and Go plans.
Paid price Higher limits start with ChatGPT Plus (₩29,000/month), with the highest limits on Pro.
Student / edu discount No
Korean KoreanUnderstands Korean instructions and explains in Korean.
Login Required
Platforms Web · Windows · macOS · Linux · Browser extension
File input None
Download output Edits files directly and shows the changes made.
Commercial use AllowedCommercial use is allowed. Check admin settings for organization accounts.

Prices may change. Currency and billing period follow the official listing; no currency conversion. Pricing page (opens in a new tab)

Who it's for

  • Developers already using ChatGPT Plus who want to start using a coding agent without extra payment
  • People who want to do other tasks while work is underway, then review the changes once results are ready
  • People who want to switch between web and terminal, continuing the same tasks in the browser

Drawbacks

  • The free tier is only for trial use; you need a paid ChatGPT plan for practical work.
  • For longer tasks, you may only notice mid-way deviations much later.
  • When handling company code, you must check organizational settings to see what gets sent to the server.

Getting started

  1. Log in with your ChatGPT account and check if your plan includes Codex.
  2. Connect your working repository or specify a folder in the terminal.
  3. Assign a goal, such as "Add logging for payment failures and write tests for it."
  4. Once finished, review each changed file and apply only what you need.
  5. Commit your changes to version control beforehand so you can revert if needed.

Similar tools

  • Claude Code Paid Claude Code is tied to a Claude subscription, while Codex is tied to a ChatGPT subscription.
  • Gemini CLI Free Gemini CLI offers generous free access, while Codex comes at no extra cost for ChatGPT subscribers.
  • GitHub Copilot Free plan GitHub Copilot auto-completes code line by line alongside you, while Codex takes on entire tasks autonomously.
  • ChatGPT Free plan ChatGPT gives you code via chat to copy and paste, while Codex directly edits files.

See also

Official link

https://openai.com/codex/ (opens in a new tab)

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