OpenAI Codex

OpenAI's coding agent across web, CLI, IDE, desktop and iOS.

Terminal agentsCloud agentsIDE extensionsOpen sourceVerified 2026-10-17

Visit OpenAI Codex ↗ Free with ChatGPT; Plus $20/mo

What is OpenAI Codex?

Codex is OpenAI's coding agent, available on the web, in an open-source CLI (Apache-2.0), an IDE extension, a desktop app and on iOS, with cloud integrations such as automatic code review and Slack. It is included in ChatGPT plans or can be used with an API key at API prices.

OpenAI Codex pricing

Plan	Price	What you get
Free	$0	Quick coding tasks; GPT-6 Luna in the desktop app (rolling out).
Go	$8/mo	Lightweight coding tasks.
Plus	$20/mo	Web, CLI, IDE, iOS; code review and Slack integrations; GPT-6.1 Sol and GPT-6 Luna.
Pro	$100, $200 or $500/mo	Higher limits, no five-hour limit currently; Ultrafast mode on the $500 tier.
Business	$20/user/mo annual (2+ users), $25 monthly	SAML SSO, no training on business data by default.
API key	API pricing	CLI, SDK and IDE only; no cloud features.

Prices in USD, excluding tax, as listed on the official pricing page on 2026-10-17.

Best for

ChatGPT subscribers who want an agent at no extra cost
Delegating parallel cloud tasks and automatic PR review
CI automation via API key

Limits & gotchas

Plus has five-hour message windows
API-key mode lacks cloud features (GitHub review, Slack)
Models rotate often; GPT-5.5 retired from Codex (ChatGPT sign-in) on Oct 14, 2026

Head-to-head

Claude Code vs OpenAI Codex →

OpenAI Codex FAQ

Is Codex included in ChatGPT?

Yes. Codex is included in ChatGPT Free, Go, Plus, Pro, Business, Edu and Enterprise, with limits that scale by plan.

Is the Codex CLI open source?

Yes, the openai/codex CLI is open source under the Apache-2.0 license.

Sources

Codex pricing (OpenAI developers) (developers.openai.com)
openai/codex on GitHub (Apache-2.0) (github.com)

Not yet verified

UnverifiedExact per-plan message limits change often; see OpenAI's pricing page.

Last verified 2026-10-17. Spot something out of date? Tell us via the newsletter reply.

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