These tools competes with

OpenAI Codex CLIvsGemini CLI

OpenAI's open-source terminal agent for autonomous coding tasks versus Google's open-source terminal AI agent

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Choose OpenAI Codex CLI when…

  • using OpenAI models and want a terminal coding agent
  • prefer open-source with full control over the agent loop
  • need to integrate with existing OpenAI API infrastructure

Choose Gemini CLI when…

  • You want a free terminal AI agent with a 1M token context window
  • You're already using Gemini and want CLI-level access
  • You want an OSS Claude Code alternative backed by Google

Side-by-side comparison

Field
OpenAI Codex CLI
Gemini CLI
Category
Coding Assistants
Coding Assistants
Type
Open Source
Open Source
Free Tier
✗ No
✓ Yes
Pricing Plans
Pay-as-you-go: OpenAI API tokens
Free: Free (Gemini API limits)
GitHub Stars
28,000
50,000
Health
90 Active
80 Active

OpenAI Codex CLI

OpenAI Codex CLI is an open-source terminal agent that applies natural language instructions to your local codebase. Running in your terminal, it reads files, writes code, runs tests, and iterates until the task is complete — powered by OpenAI's o4-mini model.

Gemini CLI

Google's open-source terminal coding agent powered by Gemini 2.5 Pro. Features a 1M token context window, native MCP server support, and is free to use within Gemini API limits. A direct Claude Code and Aider competitor from Google.

Shared Connections2 tools both integrate with

Only OpenAI Codex CLI (2)

WarpGemini CLI

Only Gemini CLI (2)

OpenAI Codex CLIGoogle Gemini API

Explore the full AI landscape

See how OpenAI Codex CLI and Gemini CLI fit into the bigger picture — 235 tools, 543 relationships, all mapped.

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