OpenAI Codex Review (2026): Pricing, Features, and How It Differs From the Old API

Estimated reading time: 8 minutes. Last verified: August 2026.

Key takeaways

• Today's "OpenAI Codex" is not the 2021 code-completion API (deprecated in 2023). It's an agentic coding product bundled into ChatGPT plans, shipped as a desktop app, CLI, IDE extension, and cloud sandbox for running tasks against your repos.
• There's no separate Codex subscription. It's included with ChatGPT Free (limited), Go ($8/month), Plus ($20/month), Pro ($100/month for 5x usage or $200/month for 20x), Business ($25/user/month), and Enterprise (custom).
• Codex CLI is open source (Apache 2.0), so you can run it locally against your own API key outside the ChatGPT bundle if you'd rather pay per-token than per-seat.
• Cloud tasks run in a sandboxed environment against connected GitHub repos, letting you queue several changes (features, tests, refactors) in parallel without keeping a terminal open.
• The tradeoff for that convenience is usage limits: Plus subscribers share Codex's local-message and cloud-task quota with a 5-hour reset window, so daily heavy users often outgrow Plus and move to Pro.

Table of contents

1. What Codex is today vs. 2021
2. Core features
3. Pricing
4. Usage limits in practice
5. Who it's for
6. FAQ

---

What Codex is today vs. 2021

If you remember "Codex" as OpenAI's 2021 code-completion API (the one that originally powered early GitHub Copilot), that product was deprecated. What's called OpenAI Codex in 2026 is a different, agentic product: you describe a task, and Codex plans, writes, tests, and reports back, either locally in a terminal or asynchronously in a cloud sandbox against your connected GitHub repos.

The naming overlap with codex.ai, an unrelated third-party domain, adds to the confusion. If you're looking for OpenAI's coding agent, it lives at chatgpt.com/codex and inside ChatGPT's desktop app, not as a standalone product with its own pricing page.

---

Core features

• Codex app: desktop agent for macOS and Windows with plugin support (Slack, GitHub, Figma).
• Cloud tasks: sandboxed repo work, features, tests, and refactors run in parallel without a local machine staying on.
• Codex CLI: open-source (Apache 2.0) terminal agent you can run locally, including against your own API key rather than a ChatGPT plan.
• Code review agent: automated PR review within your plan's usage limits.
• Multi-model routing: runs on the GPT-5.6 family (Sol, Terra, Luna) plus smaller/faster mini variants depending on task and plan.

---

Pricing

Plan	Price	What you get
Free	$0	Codex for light, occasional tasks; buy extra credits at the cap
Go	$8/month	Codex for lightweight tasks, higher limits than Free
Plus	$20/month	Codex across web, CLI, IDE extension, and iOS; roughly 15-90 local messages per 5-hour window depending on model
Pro (5x)	$100/month	5x Plus rate limits
Pro (20x)	$200/month	20x Plus rate limits, the highest individual tier
Business	$25/user/month ($20/user/month billed annually, 2-user minimum)	SAML SSO, MFA, no default training on your data, Codex via workspace credits
Enterprise	Custom	SCIM, EKM, RBAC, audit logs, data residency

Sources: openai.com/chatgpt/pricing, chatgpt.com/codex/pricing. Verified Aug 1, 2026. Business replaced the previous $30/user/month Team plan on April 2, 2026.

There's also a fourth path: running Codex CLI locally with your own OpenAI API key, paying standard per-token API rates instead of a flat monthly fee. That's cheaper for occasional use and more expensive than Plus if you're coding with it daily.

---

Usage limits in practice

Local messages and cloud tasks share a rolling 5-hour window, and the ceiling depends on which model you're running: the lighter GPT-5.6 Luna model allows roughly 50-280 messages per window on Plus, while the flagship GPT-5.6 Sol tops out around 15-90 in the same window. Pro's 5x tier roughly multiplies those numbers by five, and the 20x tier by twenty.

Practically: a developer doing a handful of focused Codex sessions per week fits comfortably on Plus. Someone running Codex as a daily background agent across multiple projects will hit Plus limits regularly and should budget for Pro from the start rather than upgrading reactively.

---

Who it's for

• ChatGPT Plus/Pro subscribers who want an agentic coding tool without a separate bill.
• Teams already on ChatGPT Business who want governed, credit-metered coding access alongside existing ChatGPT usage.
• Developers who prefer async delegated tasks (queue it, walk away, review later) over live pair-programming inside an editor like Cursor or Devin Desktop.
• Open-source contributors who want to run Codex CLI locally against their own API key rather than a ChatGPT plan.

Not a fit for teams needing a fully air-gapped, on-premises coding assistant with zero cloud data flow, since cloud tasks and most plan tiers route through OpenAI's infrastructure.

For how Codex compares as an editor-embedded alternative, see Cursor vs Windsurf and GitHub Copilot vs Cursor earlier in this series.

---

FAQ

Is OpenAI Codex the same as the old Codex API from 2021? No. The 2021 Codex API was a code-completion model, since deprecated. Today's Codex is a separate, agentic coding product bundled into ChatGPT plans, with a desktop app, CLI, and cloud sandbox.

Do I need a separate subscription for Codex? No. It's included in ChatGPT Free, Go, Plus, Pro, Business, and Enterprise plans. There's no Codex-only plan, though you can run Codex CLI against your own API key outside any ChatGPT plan.

What's the cheapest way to use Codex regularly? ChatGPT Plus at $20/month covers regular use. Occasional users may find running Codex CLI against a personal API key cheaper, paying only for tokens used.

Can Codex work entirely in the cloud without my machine running? Yes, cloud tasks run in a sandboxed environment against your connected GitHub repos and don't require your local machine or terminal to stay open.