Yes, Codex has a free plan. OpenAI's Codex pricing page lists Free at $0 a month for quick coding tasks in the desktop app, subject to rollout. Codex on the web, in the CLI and IDE extension, cloud code review and the bigger models are listed from the paid Plus plan up.
Codex is OpenAI's coding agent: you give it a task and it reads, writes and runs code for you. Lots of people assume it needs a paid ChatGPT plan. It doesn't. Here's what the free plan covers, what each paid plan adds and the small print on usage limits, all from OpenAI's own Codex pricing page, checked as of October 2026.
What the free Codex plan gives you
The Free card on the pricing page is short. It says the plan is there to explore Codex capabilities on quick coding tasks, and it lists one thing: GPT-6 Luna at Standard speed in the desktop app, subject to rollout. That last phrase matters. If you don't see Codex in your free account yet, it may not have reached you.
- Price: $0 a month
- Where it runs: the ChatGPT desktop app
- Model: GPT-6 Luna at Standard speed
- Image generation: not included. OpenAI's FAQ says image generation isn't available on the Free plan
- Cloud features such as code review in GitHub and the Slack integration: listed on Plus and above
Codex plans and prices compared
These are the plans OpenAI lists for Codex as of October 2026. Business and Enterprise sit on a separate tab of the same page.
| Plan | Price as listed | What the Codex card says |
|---|---|---|
| Free | $0 a month | Quick coding tasks, GPT-6 Luna at Standard speed in the desktop app, subject to rollout |
| Go | $8 a month | Lightweight coding tasks, GPT-6 Luna at Standard speed in the desktop app, subject to rollout |
| Plus | $20 a month | Codex on the web, CLI, IDE extension and iOS, cloud code review and Slack, GPT-6.1 Sol and GPT-6 Luna, extra usage with credits |
| Pro | From $100 a month | Everything in Plus, plans at $100, $200 or $500 a month, Ultrafast mode on Pro $500 |
| Business | $20 per user a month billed annually | For 2+ users; $25 per user a month billed monthly; admin controls and no training on business data by default |
| Enterprise and Edu | Contact sales | Priority processing, SCIM, audit logs, data residency controls |
| API key | API pricing | Codex in the CLI, SDK or IDE extension, no cloud features |
How Codex usage limits work
This is where the free plan gets tested. OpenAI doesn't give a fixed number of messages. It says your allowance depends on the model, the size of the task, how much context the agent has to hold and whether you run it locally or in the cloud. Similar looking tasks can use different amounts.
For Plus and Standard Business, OpenAI publishes rough estimates of local messages per five-hour window:
| Model | Local messages per 5 hours (Plus) |
|---|---|
| GPT-6 Astra | 5 to 45 |
| GPT-6.1 Sol | 15 to 160 |
| GPT-6.1 Terra | 35 to 285 |
| GPT-6 Sol | 15 to 150 |
| GPT-6 Luna | 350 to 3,000 |
Two things stand out. GPT-6 Luna, the model on the Free and Go cards, gets by far the biggest allowance on Plus, so it's the cheap model to run. And Pro plans currently have no five-hour limit at all, although weekly limits may still apply.
The Codex details people miss
- ChatGPT Work and Codex share one allowance. Work inside ChatGPT uses the same pricing, credits and limits as Codex, so a heavy day in one eats into the other.
- API prices aren't a guide to your plan. OpenAI says API token prices are separate from subscription usage and you shouldn't use them to estimate included tasks.
- GPT-5.5 left Codex with ChatGPT sign-in on 14 October 2026. Sessions signed in with an API key weren't affected.
- Image generation eats your limit faster. OpenAI says it uses included limits about 3 to 5 times faster on average than similar turns without images.
- Voice isn't free on top. Voice in the desktop app uses your Codex usage budget at $0.05 per minute.
What happens when you hit the Codex limit
OpenAI says that if you hit your limit in the middle of a turn, the agent can finish that turn, subject to fair use. After that, Plus and Pro users can buy extra credits instead of upgrading, and anyone can run extra local chats with an API key at standard API rates. You can see your remaining allowance in the usage dashboard, or type /status inside a Codex CLI session.
To see what the tiers include, read the ChatGPT plans.
How to make free Codex go further
- Start with small, contained jobs such as a script, a bug fix or one function, not a whole app.
- Be precise in your prompt and cut context the agent doesn't need.
- Point it at the relevant files only, instead of the whole project.
- Keep your AGENTS.md file lean, or nest smaller ones by folder on bigger projects.
- Switch off MCP servers you aren't using, because each one adds context to every message.
- Check the usage dashboard every week or two so a limit never surprises you mid-task.
Those tips come straight from OpenAI's own guidance, and they apply just as much on paid plans. If you're new to the tool, my guide on how to use OpenAI Codex walks through the desktop app and CLI step by step.
Is a paid Codex plan worth it?
If you only want Codex for the odd script or to see what an AI coding agent can do, Free is enough to find out. Go makes sense if you like it but stay on small jobs in the desktop app. Plus is the first plan that opens the CLI, the IDE extension and cloud tasks, which is where Codex starts to feel like a teammate rather than a demo. If you're weighing it against Anthropic's tool, I've compared Codex and Claude Code side by side, and I've broken down whether Claude Code is free too. After 23 years in marketing I've learned to test a tool on real work before paying, and Codex now lets you do that.
Want AI doing the heavy lifting in your marketing?
I build the systems that handle the boring 80 percent, so you get your week back. Done properly, with the human kept in.
My verdict: is Codex free?
Yes, for light use. As of October 2026 OpenAI lists a $0 Codex plan with GPT-6 Luna in the desktop app, subject to rollout. The CLI, IDE extension, cloud tasks, code review and the stronger models start on Plus at $20 a month, with Pro from $100 a month for heavy users. Try it free on a small task, watch your usage dashboard, and only pay when the limits get in the way.
Comparing coding assistants? Kiro's free tier covers a rival.
Frequently asked questions
Is Codex free to use?
Yes. OpenAI's pricing page lists a Free Codex plan at $0 a month for quick coding tasks in the desktop app, subject to rollout.
Which model does free Codex use?
The Free plan lists GPT-6 Luna at Standard speed in the desktop app.
Is the Codex CLI free?
The CLI is listed on Plus and above. You can also use it with an API key and pay standard API rates.
How much is Codex Plus?
As of October 2026 Plus was listed at $20 a month, Go at $8 a month and Pro from $100 a month.
Does Codex have usage limits?
Yes. Limits depend on the model and task. OpenAI publishes estimates per five-hour window for Plus, and weekly limits may also apply.
Can I generate images in Codex for free?
No. OpenAI's FAQ says image generation isn't available on the Free plan.
What happens when I run out of Codex usage?
You can finish the current turn. After that, Plus and Pro users can buy credits, or anyone can switch to an API key at API rates.
