What it is
OpenAI Codex is OpenAI’s coding agent, and it is comparable to Claude Code in many ways. Both are AI agents that can write, run, debug and review code, and can build software with you or for you. By writing and running code, they can do most things that a person with a computer can do.
It runs in several places, all signed in with your ChatGPT account:
- The ChatGPT desktop app, in Codex mode, works on files and folders on your computer.
- Codex on the web and in the cloud runs tasks on OpenAI-managed computers, and a cloud task can keep going while your own computer is asleep.
- The terminal (the Codex CLI) is for people comfortable in a command line.
You can also give Codex skills for jobs you repeat, connect plugins for other apps, and set it to run a task on a schedule. OpenAI’s own documentation now uses both names, “Codex” and “the ChatGPT desktop app”, so expect to see either.
What you can build with it
Describe what you want, and Codex writes the code, runs it, and checks its own work with computer and browser tools until it meets your requirements. You do not have to be a developer to ask for something, though someone needs to check what comes back. Projects that used to need a developer or an agency budget are now within reach of a small team:
- A website or campaign microsite, built from a description and previewed before it goes anywhere. Sites in Codex can build and host a small one for you.
- A platform your team runs on, such as a volunteer sign-up system, a supporter portal, or a tracker for pledges and deadlines.
- Dashboards and internal tools that pull your numbers into one place.
- Scripts and automations that move data between the systems you already use. Our link monitor case study recommends asking a coding agent such as Codex to plan and write one, then reviewing and testing the code before giving it access to any account.
- Skills for repeated work. The Animal Protection Skills repository installs in Codex, so the same instructions work whichever agent your team uses.
It also works on files that are not code. Our video guide tested OpenAI Codex on a real video.
Where it fits
For most staff, ChatGPT or Claude is the right place to start. They cover drafting, summarizing, and research. Our guide to picking the right AI tools explains why one shared choice works better than everyone picking their own.
Codex is for building. If your organization already uses ChatGPT, Codex is part of the plan. If it uses Claude, Claude Code is the closest match, and the Claude page introduces it alongside Cowork.
ChatGPT Work is a separate ChatGPT experience for longer research and deliverable tasks, so it is a different tool from Codex.
Watch-outs
- Use a paid plan. Codex is included in ChatGPT Free and Go, but OpenAI describes those as for quick, lightweight coding tasks, and the desktop app is the only place they run it. Free and Go also lack the administrative controls of a work plan. Put anyone building something real on a paid plan.
- Nonprofit usage is limited. As of October 2026, OpenAI’s nonprofit discount does not cover the Premium plan, so usage on the discounted plan is quite limited: OpenAI’s pricing page gives Standard Business seats the same estimated allowance as Plus. Building a whole site or platform is a big job, so check the allowance before you plan one. More under pricing below.
- It works on real files. Codex can change or delete files, and it can install software. The desktop app lets you choose how much it asks first. Start on the Ask for approval setting, which always asks before it edits external files or uses the internet, and work in a folder that is backed up.
- What it builds needs an owner. Test anything before it goes live, and get a technical person to review anything that handles supporter or donor data. Someone also has to keep it running and updated after Codex has built it.
- Know where your data goes. Local work runs on your device. Cloud tasks run in OpenAI-managed environments, so files you give a cloud task leave your computer. On ChatGPT Business, Enterprise, and Edu, OpenAI does not train on inputs or outputs by default. On Plus and Pro, conversations may be used unless you turn that off in ChatGPT’s data controls. Read Data security and privacy basics before using real organizational files.
- Admins set the limits on work plans. In a managed workspace, administrators can turn local Codex use and cloud tasks on or off separately. If a feature is missing, ask whoever manages your ChatGPT workspace.
- Some features are missing in Europe and the UK. Sites in Codex, which builds a small website from a description, is not available in the European Economic Area, Switzerland, or the UK. Record & Replay, a macOS feature that turns a workflow you demonstrate into a skill, was also unavailable in the EU, Switzerland, and the UK at launch.
Getting started
A realistic first 30 minutes:
- Check the plan. Use a paid one. If your organization uses ChatGPT Business or Enterprise, ask your administrator whether Codex is switched on for your workspace.
- Make a practice folder with copies of a few files. Do not point it at your only copy of anything.
- Ask it to build something small and real, such as a one-page site for a campaign, and review the preview before it goes anywhere.
- Keep the Ask for approval setting on until you trust what it does.
- When you repeat a job, ask Codex to save it as a skill. Our guide Just ask your AI shows how to get set up by asking, without menus.
Pricing snapshot
Codex is included in every ChatGPT plan, with usage limits that vary by plan. OpenAI pitches Free and Go for quick, lightweight tasks and runs Codex there in the desktop app only, with the web, terminal, and cloud features starting at Plus. We would steer organizations away from both. People who hit the limits can buy higher-usage options on individual plans, and business plans have credit plans. A long task uses much more of your allowance than a short one, and Codex shares its allowance with some other agent features on plans that have one.
Nonprofits can get a discount through OpenAI for Nonprofits, which applies to ChatGPT Business Standard seats and to Enterprise. Premium seats are not discounted, and as of October 2026 that leaves usage on the discounted plan quite limited. OpenAI’s pricing page estimates the same allowance for Plus and Standard Business seats, and says Pro plans currently have no five-hour limit. Check the current limits for your plan before you rely on Codex for a big build. What does AI actually cost? carries the current figures alongside the other vendors, and plan details change often.
