OpenCode vs Codex
Quick Answer
Codex is OpenAI’s integrated coding agent: OpenAI’s models, included with ChatGPT plans, running in the terminal, editors, and OpenAI’s cloud environments, so you can hand off tasks and pick them up from any device. OpenCode is an open-source, provider-neutral agent: any model, including local ones, with a codebase you can inspect and extend, running on your own machine.
Choose Codex for managed cloud execution and the convenience of your ChatGPT plan. Choose OpenCode for control over models, data, and the tool itself.
At a Glance
| OpenCode | Codex | |
|---|---|---|
| Maker | Anomaly (formerly SST) | OpenAI |
| License | MIT | CLI open source; service proprietary |
| Models | Dozens of providers plus local models | OpenAI models (GPT-6.1 Sol, GPT-6 Astra, and others) |
| Where it runs | Your machine (local background service in 2.0) | Terminal, IDE, desktop, and OpenAI cloud environments |
| Start tasks from a phone | No | Yes |
| How you pay | Your API keys, OpenCode pay-as-you-go, OpenCode Go, or local | ChatGPT plans (Plus and up), or API |
| Background work | Background subagents and async shell | Cloud tasks; Ultrafast mode on top Pro tier |
| Security scanning | Not built in | Codex Security Cloud (research preview) |
| Extensibility | Plugins, MCP, custom commands, Code Mode | Skills, plugins, MCP |
Model Choice
OpenCode is provider-neutral. You can use OpenAI models, Claude through an API key, Google, DeepSeek, Qwen, GLM, Kimi, MiniMax, or local models, and switch any time. That is useful for model routing: cheap models for routine edits, strong ones for hard problems.
Codex is built around OpenAI’s lineup: GPT-6.1 Sol as the near-Astra workhorse for long tasks, GPT-6 Astra for the hardest work, and faster models for quick steps. If you want other models inside the Codex app, the independent Codex Router project adds them, but that is outside OpenAI’s support.
Cloud vs Local
This is where Codex has a real advantage. Codex can run tasks in OpenAI-hosted cloud environments, reuse published environments, and let you start or check work from a phone. Long jobs do not depend on your laptop.
OpenCode 2.0 runs as a local background service that the terminal, desktop app, and editors connect to, with background subagents and asynchronous shell commands. Work continues while your machine is on, but you supply the machine. For cloud execution with OpenCode, you would run it on your own server.
Customization and Control
OpenCode is open from top to bottom: MIT license, plugins, custom commands and keybinds, MCP, and Code Mode, where agents write scripts combining MCP and API calls. You can fork it. Its Plan agent is read-only by default, which is a useful safe starting point.
Codex is customizable through skills, plugins, and MCP, and its CLI source is open, but the cloud environments and model access are OpenAI’s.
Cost
If you already pay for ChatGPT Plus or Pro, Codex usage is included up to your plan’s limits. Heavy use of GPT-6 Astra can consume a large share of an allowance in one task, and Ultrafast mode is reserved for the $500 Pro tier and eligible Enterprise and Edu plans.
OpenCode costs whatever your chosen models cost. With a cheap model or a local one it can be very inexpensive; with frontier models through APIs it can cost more than a subscription. Track cost per completed task, not just token prices.
Privacy
Codex sends code to OpenAI under your plan’s data terms; business plans exclude content from training by default. OpenCode with a local model keeps code on your machine; with hosted providers, each provider’s terms apply.
Choose OpenCode If
You want to choose your models, use local models, keep code on your hardware, avoid lock-in, or customize the agent itself.
Choose Codex If
You already pay for ChatGPT, you want cloud tasks you can start from anywhere, you want OpenAI’s strongest coding models with no setup, or you want built-in security scanning as it matures.
When Neither Is Ideal
For Anthropic’s models and automated PR review, see OpenCode vs Claude Code. For an agent inside VS Code, Cline. For a minimal Git-first tool, Aider. For Meta’s newer option, Meta Muse Code.
Final Recommendation
Codex gives you more convenience; OpenCode gives you more control. If you want an agent that works in the cloud while you are away, Codex. If you want to own your choice of models and where your code goes, OpenCode.
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Frequently Asked Questions
Is Codex open source?
The Codex CLI is open source, but Codex as a product, including its cloud environments and the ChatGPT integration, is run by OpenAI and built around OpenAI's models. OpenCode is fully open source under the MIT license and model-agnostic.
Can OpenCode use OpenAI models?
Yes, through an OpenAI API key or providers that serve OpenAI models. Third-party guides also report that OpenCode can sign in with a ChatGPT plan, consistent with OpenAI's Sign in with ChatGPT program for open-source partners; check OpenCode's docs for the current method.
Which is better for long-running or background work?
Codex, if you want it to run in the cloud. Codex tasks can run in OpenAI's cloud environments and be started from any device, including a phone. OpenCode 2.0 runs as a local background service with background subagents, so work continues while your machine is on, but it does not provide hosted cloud environments itself.
Which is cheaper?
It depends on how you pay. Codex is included with ChatGPT plans, which is good value if you already subscribe, though heavy use of GPT-6 Astra can use up allowances quickly. OpenCode is free software, and you choose the model, from expensive frontier models to cheap or local ones.
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