AI coding assistants have converged on similar underlying capability -- code completion, chat, and multi-file edits -- so the real differences between them today are mostly about how they fit into a developer's existing workflow.
Editor extensions
GitHub Copilot remains the most widely adopted option, largely because it plugs into whatever editor you already use rather than asking you to switch. Tabnine takes a similar extension-based approach but puts more emphasis on privacy and on-premises deployment, which matters for larger, security-conscious engineering teams. Codeium offers a genuinely free tier with broad editor and language support, making it a reasonable first assistant to try without a subscription commitment.
AI-first editors
Cursor and Windsurf both take a different approach: rather than being an extension bolted onto an existing editor, they are full editors (built on top of or alongside VS Code) designed around AI from the ground up, with deeper codebase-aware chat and multi-file edits than a typical extension can offer. This is a bigger workflow change than installing an extension, but it can go further precisely because the whole editor is designed around it.
Terminal and open-source options
Aider works from the command line and edits real project files directly, which suits developers who prefer staying in the terminal over a GUI-based tool. Continue is open-source and plugs into VS Code and JetBrains IDEs, a reasonable choice for teams that want more control over configuration than a closed-source tool allows.
For large teams
Sourcegraph Cody and Amazon Q Developer are both built with large codebases and existing platform investment in mind -- Cody for deep whole-codebase context, Q Developer for teams already standardized on AWS.
Explore the full list in our AI Coding Assistants directory.