Aider is a free, open-source AI pair-programming tool for the terminal. It edits files in your local git repo, auto-commits each change with a sensible message, and works with almost any LLM through your own API keys.
What is Aider?
Aider builds a map of your whole repository so the model has context in larger projects, then applies edits and commits them to git so every AI change is easy to diff and undo. It supports 100+ languages, images and web pages as context, and voice input.
It is one of the longest-running open-source coding agents, with tens of thousands of GitHub stars. You pay only for model usage.
Aider pricing
Plans as publicly listed on the official pricing page, verified 2026-10-10.
| Plan | Price | Notes |
|---|---|---|
| Aider | Free | Pay only your model provider (BYOK) |
Source: https://aider.chat/. Prices in USD, excluding tax.
Supported models
Almost any LLM via API keys, including local models. Bring-your-own-key: supported.
Claude OpenAI Gemini Open-weight Local models
Model watch: Gemini 4 Carbon — reported, unconfirmed: what we know
Features at a glance
- ✓ Agent mode
- — Autocomplete
- — Cloud / background agents
- — PR code review
- ? MCP support
- ✓ Self-host option
Interfaces: Terminal · Works with any editor via file-watch comments.
Strengths and weaknesses
＋ Strengths
- Git-native: every change is a commit you can review or revert
- Model-agnostic, including local models
- Lightweight and scriptable
- Free and open source
－ Weaknesses
- More pair-programmer than autonomous agent
- Terminal-only UI
- You manage API keys and costs
Who is Aider best for?
Git-centric developers who want precise, reviewable AI edits with any model.
Aider alternatives
Developers who want a Claude-Code-style terminal agent without vendor lock-in.
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VS Code users who want an autonomous agent with full control over models and spend.
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Head-to-head: Aider vs OpenCode · Aider vs Claude Code · Aider vs Cline