OpenAI Codex CLI vs Gemini CLI: Which AI Agent Is Better?
An in-depth comparison of OpenAI Codex CLI and Gemini CLI across output quality, autonomy, reliability, speed, value, and ease of use. Vote for your favorite.
An in-depth comparison of OpenAI Codex CLI and Gemini CLI across output quality, autonomy, reliability, speed, value, and ease of use. Vote for your favorite.
Either way, you pay for the model calls. A median coding-agent day on our gateway is 95 requests and 8.6 million tokens. The table prices every step at one model’s rate.
OpenAI Codex CLI runs on Standard Compute, where each step goes to the cheapest model that can do it: routine steps go to efficient open models, hard ones to frontier models such as Claude Fable 5.1 or GPT-6 Astra.
| Model | Typical day | Busy day |
|---|---|---|
| Claude Opus 5.5 | $7.34 | $59.10 |
| Claude Sonnet 5.5 | $3.67 | $29.55 |
| GPT-6 Luna | $0.23 | $2.43 |
Fixed monthly plans from $19. Eligible new accounts can try $0.25 of compute first, no card. Trial terms
Pick a winner in each category. You can change your vote anytime. 4 votes cast so far.
CodexGemini CLIChoose OpenAI Codex CLI if you are chatGPT subscribers who want a capable terminal agent at no extra cost. Choose Gemini CLI if you are teams on Gemini Code Assist or the paid Gemini API who want an open-source terminal agent with huge context.
In our editorial scoring, OpenAI Codex CLI leads in 5 of six categories (output quality, autonomy, reliability, value and ease of use), while Gemini CLI leads in 1 (speed). On price, OpenAI Codex CLI runs included with every chatgpt plan / api and is open source; Gemini CLI runs paid code assist licence or gemini api key (free tier ended june 2026) and is open source.
Across 4 community votes on this matchup, OpenAI Codex CLI currently leads in 2 of six categories. Cast your own vote above to move the needle.
What it costs to run Codex
Best API for Codex →
3 options compared, with prices and limits
Standard Compute sends each step to the cheapest model that can do it, on providers we vet for price, uptime and speed. Plans start at $19 a month, and eligible new accounts can try $0.25 of compute with no card. Choose your agent below to connect.
See the trial and activation steps →
More on Codex: Is Codex CLI free, and what does it cost? · How do I use Gemini in Codex CLI?
Codex CLI is OpenAI's open-source coding agent for the terminal. It edits files, runs commands in a sandbox with configurable approval modes, and can hand longer tasks off to Codex cloud to run in the background; the same agent also ships as an IDE extension and a desktop app. Usage is included with every ChatGPT plan, from Free and Go up to Plus and the $100 to $500 Pro tiers, with tighter limits on the cheaper plans, which makes it the default choice for developers already in the OpenAI ecosystem.
Gemini CLI is Google's open-source (Apache 2.0) AI agent for the terminal, with a 1M-token context window that can hold entire codebases, MCP servers, Google Search grounding, and shell command execution in an agentic loop. It is no longer free: on June 18, 2026 Google stopped serving Gemini CLI to free accounts and to Google AI Pro and Ultra subscribers, and replaced it for those users with Antigravity CLI. Gemini CLI itself is still maintained and now runs on a Gemini Code Assist Standard or Enterprise licence or a paid Gemini API key.
OpenAI Codex CLI runs on Standard Compute
