Aider vs Codex: Side-by-Side Comparison 2026
Aider vs Codex comparison 2026. Side-by-side features, pricing & capabilities.
| Feature | Aider | Codex |
|---|---|---|
| Category | Agent | Agent |
| Starting Price | Free | Free |
| Model Family | Multi-model (any) | GPT / Codex |
| Context Window | Depends on model | 400K |
| Code Completion | ✗ | ✓ |
| Chat | ✓ | ✓ |
| Inline Editing | ✗ | ✓ |
| Agentic Mode | ✓ | ✓ |
| Multi-File Editing | ✓ | ✓ |
| Terminal Commands | ✓ | ✓ |
| Browser Use | ✗ | ✗ |
| Test Generation | ✓ | ✓ |
| Debugging | ✓ | ✓ |
| Refactoring | ✓ | ✓ |
| Code Review | ✗ | ✓ |
| PR Review | ✗ | ✓ |
| Documentation | ✗ | ✓ |
| Image to Code | ✗ | ✗ |
| Voice Input | ✓ | ✗ |
| App Generation | ✗ | ✓ |
| Deployment | ✗ | ✗ |
| Git Integration | ✗ | ✓ |
| Supported IDEs | Terminal (editor-agnostic) | Codex App, VS Code, CLI |
| Open Source | Yes (Apache 2.0) | Yes (CLI) |
Pricing verified 2026-02-05. Aider pricing | Codex pricing
Overview
Aider is ai agent from Paul Gauthier (Open Source). Codex is ai agent from OpenAI. Both tools are actively maintained as of 2026.
Aider: What You Get
Open-source CLI tool for AI pair programming. Works with OpenAI, Claude, and other models to edit code in your local git repo.
- Git-aware editing
- Multi-file editing
- Model agnostic
- Voice coding
- Image support
- Linting integration
Pricing: Free. 1 plan available.
Models: Claude 3.5 Sonnet, GPT-4o, GPT-4, Gemini, DeepSeek, Groq, local (Ollama), any OpenAI-compatible
Codex: What You Get
Codex — AI Coding Agent from OpenAI. App / CLI / IDE.
- Code completions
- AI chat
- Agentic mode
- Multi-file editing
- Terminal commands
- Test generation
- Debugging
- Code review
- Git integration
- App generation
Pricing: Free / $8/mo. 6 plans available.
Models: GPT-5.3-Codex, Codex-mini-latest
Key Differences
- Category: Aider is ai agent, Codex is ai agent.
- Model family: Aider uses Multi-model (any); Codex uses GPT / Codex.
Which Should You Choose?
Choose Aider if you want Fully open-source with transparent development. Choose Codex if you want Codex handles multi-step tasks independently. Both tools are strong options — the right choice depends on your workflow and priorities.
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