Open-source CLI AI pair programmer that edits multiple files from the terminal
Aider is an open-source command-line AI pair programming tool that enables developers to make multi-file code changes using natural language from the terminal. It works with any OpenAI, Anthropic, or Ollama-compatible model, commits changes to git automatically, and supports 100+ programming languages. Aider's top performance on SWE-bench (real-world GitHub issue resolution) makes it the strongest open-source tool for automated code change tasks.
Aider is a strong fit if its core strengths match your workflow, budget, and support needs. Use the quick signals below before opening the full review.
Aider is what AI pair programming looks like for terminal-native developers: a command-line interface that accepts natural language instructions, applies multi-file changes to a git repository, and commits the results — all from the terminal, with any AI model the developer chooses to provide via API key.
Aider consistently appears among the top performers on SWE-bench — the standardised benchmark that evaluates AI tools on resolving real GitHub issues from open-source projects. This real-world issue resolution capability reflects Aider's multi-file change coordination and change verification approach rather than synthetic benchmark optimisation.
Aider requires no Aider subscription — bring an OpenAI, Anthropic, Google, or Ollama API key and the tool is free except for model API costs. This model allows developers to choose the best model for each task, switch between models as needs change, and run entirely locally with Ollama for privacy-sensitive codebases. Heavy users with efficient prompting can operate at lower cost than subscription-based tools.
Aider automatically commits each accepted change set to git with an AI-generated commit message describing the change. The result is a clean, meaningful git history where each commit corresponds to a discrete AI-assisted change — enabling easy review, rollback, and diff analysis of every AI modification made to the codebase.
Score: 8.0/10 — Best open-source CLI AI pair programmer with top SWE-bench results; terminal-only workflow excludes developers who prefer graphical IDE integration.
Free
Free billed annually
Aider is best for Developers who prefer terminal-based workflows and want multi-file AI code editing without installing a separate editor, Teams evaluating AI coding tools who want to experiment with BYOK models (Claude, GPT-4o, local Llama) before committing to a platform, Open-source contributors who want an AI pair programmer that works with their existing editor via terminal without changing their workflow.
Yes. Aider currently lists a free plan in ToolRankr data.
It has a free plan.
Aider is reviewed using ToolRankr's scoring model for ease of use, value, features, support, and overall quality. Affiliate links may earn a commission, but sponsored labels do not change editorial scoring.
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