GitHub Copilot is the original mainstream AI coding assistant. It runs in VS Code, JetBrains, Neovim, Xcode, and Visual Studio, providing inline autocomplete, chat, and (as of 2026) agent mode with Claude Sonnet 4.6 and GPT-5.4 backing. Copilot's killer feature is ubiquity — it works in every major IDE, making it the path of least resistance for most developers.
Copilot runs as an extension or plugin in your IDE. As you type, it sends context (surrounding code, nearby files, git info) to GitHub's inference backend and returns completions. Copilot Chat provides a sidebar for conversations, and Copilot Agent (2026) can autonomously work on issues via multi-step workflows. Integration with GitHub Pull Requests lets Copilot review, summarize, and suggest changes on PRs directly in the GitHub UI.
Individual: $10/month or $100/year. Business: $19/user/month. Enterprise: $39/user/month with advanced features like self-hosted models and audit logs. Free for verified students and OSS maintainers.
Everyone — 2M+ paid subscribers, including most Fortune 500 engineering teams. The default choice when you don't want to think about it.