Gemini CLI vs OpenAI Codex CLI — Feature Comparison
Quick answer: Gemini CLI supports 18 of 18 tracked features; OpenAI Codex CLI supports 16 of 18. Matrix last updated July 19, 2026.
Verdict: Gemini CLI vs Codex CLI
Gemini CLI is the more feature-complete choice for most developers, but OpenAI Codex CLI is a credible alternative for those already invested in the OpenAI ecosystem. Gemini CLI covers all 18 tracked features, including multi-file editing and JetBrains IDE integration, while OpenAI Codex CLI supports 16 of 18 — a meaningful gap if either of those missing capabilities is part of your daily workflow. Gemini CLI also has a substantially longer release history with over 300 tracked releases, signaling a more mature codebase and a longer track record of iteration. Both tools show active recent development, with OpenAI Codex CLI actually shipping slightly more releases in the last 90-day window, suggesting its Rust-based rewrite is moving quickly and closing ground fast. The architectural difference matters here: OpenAI Codex CLI's Rust foundation may appeal to developers who prioritize performance and binary portability, while Gemini CLI's breadth of IDE and multi-file support makes it the stronger pick for teams using JetBrains tools or tackling complex, cross-file refactors. Neither tool is a bad choice — the decision ultimately comes down to which gaps you can tolerate and which integrations you depend on. If you need the fullest feature surface and JetBrains compatibility right now, Gemini CLI is the safer bet; if you're comfortable tracking a fast-moving project and are primarily OpenAI-stack oriented, Codex CLI is worth watching closely.
Choose Gemini CLI if: Choose Gemini CLI if you work across multiple files simultaneously, rely on JetBrains IDEs, or want the broadest tracked feature coverage with a long, proven release history.
Choose OpenAI Codex CLI if: Choose OpenAI Codex CLI if you are deeply integrated with the OpenAI ecosystem, value a Rust-based architecture for performance and portability, and are comfortable adopting a rapidly evolving tool.
Key differences
- Gemini CLI supports all 18 tracked features; OpenAI Codex CLI supports 16, missing Multi-file Editing and JetBrains integration
- Gemini CLI has a longer release history (302 tracked releases vs. 132), indicating greater overall maturity
- OpenAI Codex CLI shipped slightly more releases in the recent 90-day window, reflecting an accelerating development pace
- OpenAI Codex CLI is built in Rust, offering potential performance and portability advantages over Gemini CLI's architecture
- Gemini CLI's JetBrains support makes it the clear pick for IntelliJ, PyCharm, or WebStorm users
At a glance
| Tool | Latest version | Release date | Releases tracked |
|---|---|---|---|
| Gemini CLI | v0.51.0 | July 16, 2026 | 304 |
| OpenAI Codex CLI | rust-v0.144.6 | July 18, 2026 | 140 |
Core Editing
Multi-file editing, streaming, undo capabilities
| Feature | Gemini CLI | Codex CLI |
|---|---|---|
| Multi-file Editing — Edit multiple files in a single operation | ✓ since v0.22.0 | — |
| Streaming Output — Real-time streaming of AI responses | ✓ since v0.44.0 | ✓ since rust-v0.142.0 |
| Undo/Redo — Ability to undo and redo changes | ✓ since v0.49.0 | ✓ since rust-v0.144.2 |
| Diff View — Visual comparison of changes | ✓ since v0.51.0 | ✓ since rust-v0.144.6 |
Terminal Integration
Shell and command execution support
| Feature | Gemini CLI | Codex CLI |
|---|---|---|
| Command Execution — Run shell commands | ✓ since v0.49.0 | ✓ since rust-v0.144.5 |
| Shell Integration — Integration with user shell environment | ✓ (PTY (pseudo-terminal) support and Termux relaunch fix in v0.45.0 indicate shell integration) | ✓ since rust-v0.143.0 |
| Background Tasks — Run tasks in background | ✓ since v0.49.0 | ✓ since rust-v0.143.0 |
MCP Support
Model Context Protocol server and client capabilities
| Feature | Gemini CLI | Codex CLI |
|---|---|---|
| MCP Client — Connect to MCP servers | ✓ since v0.47.0 | ✓ since rust-v0.144.0 |
| MCP Server — Expose as MCP server | ✓ since v0.44.0 | ✓ since rust-v0.143.0 |
| Custom Tools — Define and use custom tools | ✓ since v0.30.0 | ✓ since rust-v0.143.0 |
IDE Integrations
VS Code, JetBrains, and other editor support
| Feature | Gemini CLI | Codex CLI |
|---|---|---|
| VS Code — Visual Studio Code integration | ✓ since v0.51.0 | ✓ since rust-v0.136.0 |
| JetBrains — IntelliJ/WebStorm integration | ✓ since v0.41.0 | — |
| Vim/Neovim — Vim or Neovim integration | ✓ since v0.45.0 | ✓ since rust-v0.136.0 |
| Web UI — Browser-based interface | ✓ since v0.51.0 | ✓ since rust-v0.144.0 |
Agentic Features
Planning, tool use, and autonomous capabilities
| Feature | Gemini CLI | Codex CLI |
|---|---|---|
| Planning Mode — Plan before executing changes | ✓ since v0.43.0 | ✓ since rust-v0.142.0 |
| Autonomous Mode — Extended autonomous operation | ✓ since v0.50.0 | ✓ since rust-v0.144.2 |
| Task Decomposition — Break complex tasks into steps | ✓ since v0.41.0 | ✓ since rust-v0.143.0 |
| Context Management — Manage context across conversations | ✓ since v0.51.0 | ✓ since rust-v0.144.6 |
Feature timeline: who shipped first
First release where Gemini CLI and Codex CLI each shipped a notable feature, and which tool led.
| Feature | Gemini CLI | Codex CLI | Who led |
|---|---|---|---|
| Custom Slash Commands | February 10, 2026 | August 20, 2025 | Codex CLI first, 175d ahead |
| Planning Mode | — | January 25, 2026 | only Codex CLI |
| Hooks | January 14, 2026 | May 8, 2026 | Gemini CLI first, 114d ahead |
| Subagents / Parallel Agents | April 1, 2026 | January 25, 2026 | Codex CLI first, 66d ahead |
| Skills / Plugins | January 21, 2026 | December 10, 2025 | Codex CLI first, 41d ahead |
| Sandboxing / Permission Modes | — | August 7, 2025 | only Codex CLI |
| MCP Support | January 7, 2026 | July 23, 2025 | Codex CLI first, 168d ahead |
| Image / Vision Input | — | December 2, 2025 | only Codex CLI |
| Extended Thinking | — | July 9, 2025 | only Codex CLI |
| Web Search / Fetch | — | June 9, 2026 | only Codex CLI |
| Project Memory Files | — | February 12, 2026 | only Codex CLI |
| Git / PR Integration | — | May 7, 2026 | only Codex CLI |
| Headless / Non-interactive Mode | — | July 19, 2025 | only Codex CLI |
| Voice Input | — | February 25, 2026 | only Codex CLI |
| Checkpoints / Rewind | — | December 15, 2025 | only Codex CLI |
| Todo / Task List | — | May 21, 2026 | only Codex CLI |
Release velocity
Havoptic tracks 304 Gemini CLI releases and 140 Codex CLI releases. See release frequency charts for side-by-side velocity analysis, or browse the Gemini CLI changelog and OpenAI Codex CLI changelog.
Data source
Feature data is maintained in feature-matrix.json under a CC-BY-4.0 license. Release data comes from releases.json. Both are updated daily. See the methodology page for details on sourcing and human review.