StartupAlternatives
Paid · Included with ChatGPT Plus $20/mo or API usage

ChatGPT Codex

OpenAI's coding agent.

Visit ChatGPT Codex
What is ChatGPT Codex?
ChatGPT Codex is OpenAI's software engineering agent, available as a terminal CLI, an IDE extension, and a cloud agent in ChatGPT.
What does it do?
Reads a repository, writes and edits code, runs commands and tests, and proposes changes as pull requests. The cloud version runs tasks in sandboxed containers in parallel; the CLI works locally against your checkout.
Who is it for?
Developers and engineering teams already working in OpenAI's ecosystem who want an agent to handle refactors, bug fixes, and routine pull requests.
What are the alternatives to ChatGPT Codex?
Claude Code is Anthropic's terminal agent; Cursor and Windsurf are AI-first editors; Aider, Cline, and OpenCode are open-source agents you point at your own model.

Pricing

Included with ChatGPT Plus $20/mo or API usage

Paid

Alternatives to ChatGPT Codex

Tools that solve the same problem as ChatGPT Codex, including the ones it's listed against.

Claude Code website preview

Anthropic's agentic coding tool in your terminal.

Included with Claude Pro $20/mo or API usage
Cursor website preview

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$20/mo (Pro)
Aider website preview

AI pair programming in your terminal.

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Cline website preview

Open-source coding agent for VS Code.

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Roo Code website preview

Open-source autonomous coding agent.

OpenCode website preview

Open-source terminal coding agent.

Goose website preview

Open-source local AI agent.

Crush website preview

Charm's terminal coding agent.

Continue.dev website preview

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Cody by Sourcegraph website preview

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$9/seat/mo (Pro)
Windsurf website preview

Codeium's AI editor.

$15/mo (Pro)
Zed website preview

Fast, collaborative code editor.

FreeOSS
Replit website preview

Cloud IDE with AI agents.

$25/mo (Core)
Void Editor website preview

Open-source Cursor alternative.

ChatGPT Codex — alternative to Claude Code & Cursor · Startup Alternatives