Side-by-side comparison of Codex CLI (OpenAI) and Gemini CLI (Google) - pricing, key features, ideal use cases, recent updates, and verdicts.
01Quick answer
Codex CLI (Freemium) is best for handling mechanical, well-scoped engineering tasks like updating dependencies, refactoring based on clear patterns, writing unit tests, and CI/CD configuration. Gemini CLI (Freemium) is best for enterprise organizations and professional developers using Gemini Code Assist or Google Cloud infrastructure who require a persistent, agentic coding assistant in the terminal.
02The two tools
Codex CLI
OpenAI Free free to use · FreemiumCodex CLI is an open-source terminal-based coding agent that allows developers to automate engineering tasks, perform code reviews, and interact with codebases directly from the command line. It supports multi-agent workflows, local file system operations, and integration with external tools via the Model Context Protocol (MCP).
Gemini CLI
Google Free free to use · FreemiumGemini CLI is an open-source terminal agent that provides access to Gemini models for coding and general tasks directly from the command line. It utilizes a reason and act (ReAct) loop with local or remote MCP servers to perform complex operations like debugging, codebase exploration, and workflow automation.
03How to choose
Choose Codex CLI if
Handling mechanical, well-scoped engineering tasks like updating dependencies, refactoring based on clear patterns, writing unit tests, and CI/CD configuration.
Skip if: Complex architectural decisions, performance optimization involving deep framework internals, or tasks requiring high-level abstract reasoning that benefits from specialized competitive alternatives.
Choose Gemini CLI if
Enterprise organizations and professional developers using Gemini Code Assist or Google Cloud infrastructure who require a persistent, agentic coding assistant in the terminal.
Skip if: Individual users on free tiers, Google One subscribers, or developers seeking optimization for Gemini 4+ series models, as this tool is currently restricted to older model generations.
04Detailed comparison
| Codex CLI | Gemini CLI | |
|---|---|---|
| Company | OpenAI | |
| Category | Terminal & CLI Agents | Terminal & CLI Agents |
| Pricing | Freemium Included in ChatGPT Plus, Pro, Business, and Enterprise plans. API usage is billed per token. Free and Go plans have limited access to specific models. | Freemium Available via Gemini Code Assist Standard/Enterprise subscriptions, Vertex AI pay-as-you-go, or Gemini API keys. Free individual tiers are no longer supported for this specific tool as of June 18, 2026. |
| Key features |
|
|
| Best for | Handling mechanical, well-scoped engineering tasks like updating dependencies, refactoring based on clear patterns, writing unit tests, and CI/CD configuration. | Enterprise organizations and professional developers using Gemini Code Assist or Google Cloud infrastructure who require a persistent, agentic coding assistant in the terminal. |
| Not ideal for | Complex architectural decisions, performance optimization involving deep framework internals, or tasks requiring high-level abstract reasoning that benefits from specialized competitive alternatives. | Individual users on free tiers, Google One subscribers, or developers seeking optimization for Gemini 4+ series models, as this tool is currently restricted to older model generations. |
| Recent updates | Introduced GPT-6.1-Terra (Oct 2026) for efficient code tasks and expanded model support including GPT-6.1-Sol and Astra. Ongoing improvements include enhanced terminal UI formatting, refined approval modes, and expanded MCP integration capabilities. | Version 0.64.0 introduced atomic operations and improved state persistence for recovery. Version 0.63.0 added support for autonomous plan execution in non-interactive modes. |
| Verdict | A robust, open-source terminal agent that excels at offloading repetitive development work, though it functions best as part of a multi-tool setup rather than as a replacement for all complex coding tasks. | A robust, enterprise-focused terminal agent that excels at integrated development workflows on Google Cloud but is not recommended for users prioritizing the latest model performance or free-tier individual access. |
05FAQ
Is Codex CLI or Gemini CLI free?+
Codex CLI is Freemium; Gemini CLI is Freemium. Check each tool's detail page for full pricing breakdowns.
Which should I choose, Codex CLI or Gemini CLI?+
Codex CLI is best for Handling mechanical, well-scoped engineering tasks like updating dependencies, refactoring based on clear patterns, writing unit tests, and CI/CD configuration. Gemini CLI is best for Enterprise organizations and professional developers using Gemini Code Assist or Google Cloud infrastructure who require a persistent, agentic coding assistant in the terminal.
What is the main difference between Codex CLI and Gemini CLI?+
Codex CLI (OpenAI) is listed as Terminal & CLI Agents; Gemini CLI (Google) is listed as Terminal & CLI Agents. Codex CLI is an open-source terminal-based coding agent that allows developers to automate engineering tasks, perform code reviews, and interact with codebases directly from the c… By contrast, Gemini CLI is an open-source terminal agent that provides access to Gemini models for coding and general tasks directly from the command line. It utilizes a reason and act (ReAct)…