Grammar Guardian is a free Chrome extension designed to improve your writing by offering AI-powered grammar corrections and writing suggestions. It seamlessly integrates into any text field on websites, allowing users to check grammar, fix spelling errors, and receive phrasing suggestions. The extension supports various AI providers, including OpenRouter, Anthropic, OpenAI, and Google Gemini, enabling users to utilize their own API keys for personalized writing assistance.

The tool features an inline check button that appears in text fields, providing easy access to grammar checking. Users can view detailed explanations of corrections, apply fixes with a click, or copy the corrected text. Additional features include customizable writing tones, style suggestions, and a right-click context menu for on-the-spot grammar checks. With a strong emphasis on privacy, Grammar Guardian ensures that user data remains secure and private.