ChatGPT vs Codex: Side-by-Side Comparison 2026

ChatGPT vs Codex comparison 2026. Side-by-side features, pricing & capabilities.

ChatGPT is an AI assistant from OpenAI — ai assistant with powerful coding capabilities. Codex is an AI agent and a CLI-based coding agent from OpenAI — asynchronous autonomous coding agent.

ChatGPT

ChatGPT — Conversational AI from OpenAI. General + Coding.

  • AI chat
  • Test generation
  • Debugging
  • Code review

Free / $8/mo · 6 plans

Codex🏆 Approved

OpenAI's autonomous coding agent. Available via web, desktop app (macOS), CLI (macOS/Linux/Windows), and VS Code extension.

  • Code completions
  • AI chat
  • Agentic mode
  • Multi-file editing
  • Terminal commands

Free / $8/mo · 6 plans

Feature ChatGPT Codex
Category AssistantAgent / CLI
Starting Price Free Free
Model Family GPT / o-seriesGPT / Codex
Agentic Mode
Multi-File Editing
Terminal Commands
Voice Input
Git Integration
Open Source NoYes (CLI)

Pricing verified Feb 25, 2026. ChatGPT pricing | Codex pricing

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Key Differences

  • Category: ChatGPT is an AI assistant; Codex is an AI agent and a CLI-based coding agent.
  • Model family: ChatGPT uses GPT / o-series; Codex uses GPT / Codex.
  • Agentic mode: Codex supports agentic mode; ChatGPT does not.
  • Open source: ChatGPT: No. Codex: Yes (CLI).
  • Bring your own key: Codex supports BYOK; ChatGPT does not.
  • Platforms: ChatGPT runs on Android, Web, Windows, iOS, macOS; Codex runs on Linux, Web, Windows (experimental), macOS.
  • Capabilities: Codex has multi-file editing; Codex has terminal commands; ChatGPT has voice input.

Which Should You Choose?

Choose ChatGPT if you want AI-powered coding assistance. Choose Codex if you want asynchronous coding tasks you can fire off and review when ready. Read our full reviews to see which fits your workflow.

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