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Gemini CLI vs OpenAI Codex
Short answer: Pick Gemini CLI if you want terminal-first AI agent; pick OpenAI Codex if you want multi-agent coding workflows. Gemini CLI has a free plan; OpenAI Codex has a free plan, paid from $20/month.
Gemini CLIGoogle's open-source AI agent for the terminal
OpenAI CodexOpenAI's coding agent for the terminal, IDE and cloudWhich to pick
Pick Gemini CLI if you want…
- Terminal-first AI agent
- Open-source code (google-gemini/gemini-cli on GitHub, Apache-2.0 license)
- Integrations with Homebrew, MacPorts or Anaconda (on Gemini CLI's list, not OpenAI Codex's)
Pick OpenAI Codex if you want…
- Multi-agent coding workflows
- OpenAI-based coding agent
- Integrations with ChatGPT account or Plugins (on OpenAI Codex's list, not Gemini CLI's)
Side by side
- What it is
- Gemini CLI:Gemini CLI is an open-source AI agent that lets you run Google Gemini models directly from the terminal.
- OpenAI Codex:OpenAI Codex is an AI coding agent that assists across terminal, IDE, and cloud for planning, building, refactoring, reviewing, and releasing code.
- Best for
- Gemini CLI:Terminal-first AI agent
- OpenAI Codex:Multi-agent coding workflows
- Who it’s for
- Gemini CLI:Developers who work primarily in the command line and need AI assistance.
- OpenAI Codex:Developers and engineering teams needing AI-assisted coding and code review.
- Pricing
- Gemini CLI:Freemium
- OpenAI Codex:Freemium
- Starting price
- Gemini CLI:—
- OpenAI Codex:$20/month (Plus)
- Plans
- Gemini CLI:—
- OpenAI Codex:Plus $20 per month · Pro $100 per month · Business $20 per user / month
- Open source
- Gemini CLI:Yes, 107,216 GitHub stars
- OpenAI Codex:—
- Works with
- Gemini CLI:Homebrew, MacPorts, Anaconda
- OpenAI Codex:ChatGPT account, Plugins
Gemini CLI features
- Free tier. 60 requests per minute and 1,000 requests per day with a personal Google account.
- Gemini 3 models. Access to Gemini 3 with improved reasoning and up to 1 M token context.
- Built-in tools. Google Search grounding, file operations, shell commands, and web fetching.
- MCP support. Model Context Protocol enables custom integrations and extensions.
- Multiple install methods. Install via npx, npm, Homebrew, MacPorts, or Anaconda.
- Open source. Released under the Apache 2.0 license.
OpenAI Codex features
- Parallel agent execution. Runs multiple coding agents simultaneously, using tools to verify work until requirements are met.
- Reusable cloud environments. Keeps tasks running in the cloud with per-repo environments that persist across devices.
- Automated PR reviews. Scans pull requests, surfaces findings, and answers questions to accelerate code review.
- Plugin ecosystem. Connects to external tools and adds specialized capabilities via plugins.
- Cross-platform access. Available in ChatGPT, IDE extensions, CLI, and web, all linked to a single account.
- Secure shared workspaces. Business plan offers admin controls and shared repositories for team collaboration.
Gemini CLI vs OpenAI Codex FAQ
What is the difference between Gemini CLI and OpenAI Codex?+
OpenAI Codex provides OpenAI models for terminal and IDE, while Gemini CLI uses Google’s Gemini models.
Should I use Gemini CLI or OpenAI Codex?+
Pick Gemini CLI if you want terminal-first AI agent, open-source code (google-gemini/gemini-cli on GitHub, Apache-2.0 license) or integrations with Homebrew, MacPorts or Anaconda (on Gemini CLI's list, not OpenAI Codex's). Pick OpenAI Codex if you want multi-agent coding workflows, OpenAI-based coding agent or integrations with ChatGPT account or Plugins (on OpenAI Codex's list, not Gemini CLI's).
Is Gemini CLI or OpenAI Codex free?+
Gemini CLI has a free plan and paid plans. OpenAI Codex has a free plan; paid plans start at $20/month (Plus).
Is Gemini CLI or OpenAI Codex open source?+
Gemini CLI is open source (google-gemini/gemini-cli on GitHub, Apache-2.0 license). DevHunt has no public source repository on record for OpenAI Codex.
Do Gemini CLI and OpenAI Codex integrate with the same tools?+
Their integration lists don't overlap: Gemini CLI lists Homebrew, MacPorts and Anaconda; OpenAI Codex lists ChatGPT account and Plugins.
On DevHunt
Based on each tool's website and DevHunt data. Details may change; check the official sites.