OpenAI · Coding
Codex
Codex is OpenAI's coding agent, and it works through tasks in the cloud on its own.
Open Codex openai.com/codex ↗
- Costs
- Free with ChatGPT; Plus $20/mo, Pro from $100
- Runs on
- GPT-6.1 Terra, GPT-6 Astra, GPT-6 Sol, GPT-6 Luna
- Best for
- Coding, Agents
Where it shines
- Free ChatGPT accounts can use Codex with GPT-6 Luna.
- Plus users can switch between Terra, Astra and Sol.
Where it struggles
- Pro users reportedly get half as much Codex usage from Oct 30.
See the models it runs
OpenAI
GPT-6 Astra
GPT-6 Astra is OpenAI's strongest thinker and the pick for hard math and science problems.
Hard problems
- Price
- $10 in · $50 out
- Context
- 1.1M
OpenAI
GPT-6.1 Terra
GPT-6.1 Terra is OpenAI's new mid-tier model for computer use, and its early math scores are strong.
Hard problems
- Price
- $1 in · $5 out
- Context
- 1.1M
Compare it with these apps
xAI
Grok Bot
Grok Bot gives you AI teammates that keep working on a cloud computer after you log off.
Agents
- Costs
- In SuperGrok Heavy, Cursor Ultra or Teams Premium
Anthropic
Claude Code
Claude Code puts Opus 5.5 to work inside your codebase and terminal.
CodingAgentsWebsites & apps
- Costs
- No free tier; Pro $20/mo, Max $100 or $200/mo
- Runs on
- Claude Opus 5.5, Sonnet 5.5, Haiku 5.5
Anysphere
Cursor
Cursor is an AI code editor for day-to-day work in your own project.
Coding
- Costs
- Free; Plus $8, Premium $30/mo
- Runs on
- Cursor's own models and Grok; Claude, GPT, Gemini at API price
GitHub
GitHub Copilot
GitHub Copilot works inside the GitHub tools and editors you already use.
Coding
- Costs
- Free; Pro $10/mo, Pro+ $39/mo
- Runs on
- Your pick of models, incl. GPT-6.1 Terra and Gemini 4 Argon
Leaderboards don’t rank apps, so Claude writes this page from its own web research. Prices and plans change often; check openai.com/codex before you buy.