Codex
OpenAI's coding agent that lives in your IDE and can run in the cloud
What is Codex?
Codex is OpenAI's coding agent delivered as an IDE extension plus a Codex Cloud surface, letting developers either pair-program in VS Code, Cursor, Windsurf, and JetBrains IDEs or delegate longer tasks to the cloud and check back later. It supports three approval modes (Chat, Agent, Agent Full Access) and adjustable reasoning effort. Access is bundled into ChatGPT Plus, Pro, Business, Edu, and Enterprise — there is no standalone Codex subscription.
Coding agents and AI developer tools for writing, reviewing, debugging, and shipping software.
See the full AI Coding guide to compare more tools, buyer criteria, and related workflows.
Use cases to evaluate
Pair-programming inside VS Code, Cursor, or JetBrains IDEs
Delegating long refactors to Codex Cloud and reviewing results later
Debugging unfamiliar codebases by asking the agent to trace flows
Generating and editing images directly inside the editor
Fit to evaluate
Developers already on ChatGPT Plus or Pro
Teams standardized on JetBrains or VS Code that want one bundled agent
ChatGPT Enterprise customers extending the subscription to coding
Engineers who want both inline and cloud-delegated agent workflows
Business fit
Right for you if you already pay for ChatGPT Plus or higher and want a coding agent that works inside your existing IDE without a new subscription. Skip if you are deep in the Anthropic ecosystem with Claude Code or need a tool with separate enterprise admin controls outside ChatGPT's plans. Approval modes matter — Agent Full Access lets it run commands unattended, which is powerful and risky in the same breath.
How to evaluate Codex
Use this category when software delivery speed, code review, or developer leverage is a business constraint.
Confirm the exact workflow
Map Codex to one concrete workflow first, such as pair-programming inside vs code, cursor, or jetbrains ides. Avoid buying before the owner, trigger, output, and success metric are clear.
Check category fit
Test with your actual repository and review diff quality.
Compare practical alternatives
Shortlist Codex against Claude Code, Cursor, GitHub Copilot so the decision is based on fit, effort, and workflow ownership rather than brand recognition alone.
Validate cost and rollout effort
No separate price — included with ChatGPT Plus ($20/mo), Pro ($200/mo), Business, Edu, and Enterprise plans. Also confirm implementation time, support needs, and whether the technical setup matches your team.
Compare Codex with alternatives
Use this quick comparison before booking demos or moving data into a new system.
| Primary workflow | Pair-programming inside VS Code, Cursor, or JetBrains IDEs, Delegating long refactors to Codex Cloud and reviewing results later |
|---|---|
| Best-fit team | Developers already on ChatGPT Plus or Pro, Teams standardized on JetBrains or VS Code that want one bundled agent |
| Implementation effort | Technical setup and maintenance profile |
| Pricing check | Free plan + paid plans |
| Closest alternatives | Claude CodeCursorGitHub CopilotReplit |
Codex pricing
| Model | Free plan + paid plans |
|---|---|
| Snapshot | No separate price — included with ChatGPT Plus ($20/mo), Pro ($200/mo), Business, Edu, and Enterprise plans. |
| Checked |
Common questions about Codex
What is Codex?
Codex is OpenAI's coding agent delivered as an IDE extension plus a Codex Cloud surface, letting developers either pair-program in VS Code, Cursor, Windsurf, and JetBrains IDEs or delegate longer tasks to the cloud and check back later. It supports three approval modes (Chat, Agent, Agent Full Access) and adjustable reasoning effort. Access is bundled into ChatGPT Plus, Pro, Business, Edu, and Enterprise — there is no standalone Codex subscription.
What is Codex used for?
Common use cases: Pair-programming inside VS Code, Cursor, or JetBrains IDEs; Delegating long refactors to Codex Cloud and reviewing results later; Debugging unfamiliar codebases by asking the agent to trace flows; Generating and editing images directly inside the editor.
How much does Codex cost?
No separate price — included with ChatGPT Plus ($20/mo), Pro ($200/mo), Business, Edu, and Enterprise plans.
Who is Codex best for?
Codex fits Developers already on ChatGPT Plus or Pro, Teams standardized on JetBrains or VS Code that want one bundled agent, ChatGPT Enterprise customers extending the subscription to coding, Engineers who want both inline and cloud-delegated agent workflows. Right for you if you already pay for ChatGPT Plus or higher and want a coding agent that works inside your existing IDE without a new subscription. Skip if you are deep in the Anthropic ecosystem with Claude Code or need a tool with separate enterprise admin controls outside ChatGPT's plans. Approval modes matter — Agent Full Access lets it run commands unattended, which is powerful and risky in the same breath.
What are alternatives to Codex?
Common alternatives to Codex include Claude Code, Cursor, GitHub Copilot, Replit, Windsurf, Tabnine.