Claude Code is Anthropic’s coding agent and Codex is OpenAI’s. Both edit code, run commands and work across a repository, and which one suits you depends on the plan you already pay for and the model you prefer. You do not have to choose: they can work side by side, and the one that is not out of usage can carry on. Facts below are from each maker’s own pages, checked on 4 November 2026.
Why not just use both?
Your work shouldn’t own your day, and a usage limit shouldn’t decide when it stops. People who use one coding agent all day eventually meet its limit. People who keep a second one ready just carry on with that.
Published comparisons of the two disagree on benchmarks and on context sizes, depending on the source and the date, so we do not quote a score or name a winner. What follows is what each maker says about its own product.
How do they differ?
| Claude Code | Codex | |
|---|---|---|
| Made by | Anthropic | OpenAI |
| Where it runs | Terminal, IDE extensions, a desktop app and the web | The Codex CLI, an IDE extension, the ChatGPT desktop, mobile and web apps, and Codex cloud |
| Cheapest plan with it | Claude Pro: $20 a month, or $17 a month billed yearly. The free plan does not include it | Included in ChatGPT Free ($0) and Go ($8 a month), then Plus ($20 a month); the Free plan’s limits are not stated on the pricing page |
| Limits | Pro and Max plans have a five-hour session limit and a weekly limit, shared with Claude | OpenAI’s pricing page describes a five-hour window of local messages for Plus and Standard Business plans, a weekly limit that may apply, and extra credits you can buy |
| Project instructions | CLAUDE.md. It also reads AGENTS.md when there is no CLAUDE.md, on current versions | AGENTS.md |
Last checked: 4 November 2026
Sources, all read on 4 November 2026: Anthropic’s pricing, the Claude Code docs, Anthropic’s help article on Pro and Max limits, its memory docs, OpenAI’s pricing and its AGENTS.md page. Plans and limits change often; check them before you buy.
Which one should you start with?
- If you already pay for a Claude plan, Claude Code is included from Pro, so you can try it without a new bill.
- If you already have ChatGPT, Codex is included in your plan, including the free one, with limits that depend on the plan.
- If you want one set of project instructions for both, write an AGENTS.md: Codex reads it, and Claude Code reads it when there is no CLAUDE.md.
For the full three-way view with Cursor, see Claude Code vs Codex vs Cursor. For what to do the moment one stops, see the guides on Claude Code and Codex usage limits.
How do you use both?
- Give each agent its own copy of the repository, such as a git worktree on its own branch, so they cannot overwrite each other.
- Keep one AGENTS.md that both read, so the same project rules reach both.
- Split the work so no two agents change the same files, and review each diff before it merges.
- When one reaches its usage limit, pass the task to the other with a note of what was done and what is left.
Friday does that last step for you. It runs Claude Code and Codex side by side on your own computer, with a task board, and each agent can work in its own git worktree. When one reaches its usage limit, the task moves to another agent with a record of what the first did and changed. See how to use Claude Code, Codex and Cursor together, and how to run multiple coding agents at once.
What is Friday?
Friday is a free, open-source (MIT) harness for coding agents that work as a team. It runs on your own computer with no account: the desktop app for macOS, Windows and Linux, or one command with Node.js 22 and Git.
- Claude Code, Codex, Cursor and 13 more coding tools (16 by name, plus any ACP agent) run side by side on their own plans and sign-ins.
- One agent splits a job into a task board, the others pick up tasks, and every finished task is checked before it counts as done.
- Agents message each other as they work, and each can work in its own copy of the repository.
- When a tool runs out of usage mid-task, the task moves to the agent best placed to finish it.
- Review each run’s changes line by line, with git built in.
- No account; anonymous usage counts you can turn off; it listens on 127.0.0.1 only.
Install it with npx github:splashxmoon/friday or from GitHub; see the docs. Friday Team, the hosted version for several people in one session, is available to companies: talk to us.