Gemini CLI vs OpenAI Codex

OpenAI Codex provides OpenAI models for terminal and IDE, while Gemini CLI uses Google’s Gemini models.

Gemini CLIGoogle's open-source AI agent for the terminal

OpenAI CodexOpenAI's coding agent for the terminal, IDE and cloud

Which 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
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

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

Gemini CLI

Listed by DevHunt

Gemini CLI on DevHunt →Gemini CLI alternatives

OpenAI Codex