AI Writing Assistant

Fix grammar, rewrite, translate and find synonyms on any site with Claude or GPT. Select text, right-click, done.

AI Writing Assistant brings a professional writing editor to every text field in your browser. Select any text on any website (an email in Gmail, a message in Slack, a comment on GitHub, a post on LinkedIn), right-click, and choose what you need: fix grammar and spelling, improve the writing, shorten it, make it more formal or more casual, translate it, or get synonyms and antonyms for a single word. A floating panel shows two or three suggestions right next to your selection, and one click replaces the original text in place. No copy-pasting, no switching tabs. MADE FOR PEOPLE WHO WRITE IN A SECOND LANGUAGE Pick the language you want help writing in (American English, Spanish, Brazilian Portuguese or French) and your native language, and the two translate actions adapt automatically: one translates into your working language, the other back into your own. Suggestions are tuned to each language's regional variety, so corrections in Spanish keep the voseo and translations into English sound like a native wrote them. WRITING THAT STILL SOUNDS LIKE YOU Rewrites preserve your casing, punctuation, rhythm and voice, so the result doesn't read like AI. Every prompt is fully customizable per action from the options page. A keyboard shortcut (Cmd/Ctrl+Shift+U, remappable) runs the "improve" action instantly on whatever you have selected. FEATURES - Works in standard inputs, textareas and rich editors (Gmail, Slack, Notion, Linear) - 9 actions: fix grammar, improve, shorten, formal tone, casual tone, synonyms, antonyms, and two-way translation between your working and native languages - 4 languages: American English, Español (Argentina), Português (Brasil), Français - 2-3 alternative suggestions per action, one click to replace - Bring your own key: Anthropic (Claude) or OpenAI (GPT), model selectable - Custom prompts per action and per language, with sensible defaults you can edit HOW TO USE 1. Add your Anthropic or OpenAI API key in the extension options (one-time setup) 2. Select text in any editable field on any site 3. Right-click, open "AI Writing Assistant" and pick an action 4. Click the suggestion you like — it replaces your selection in place PRIVACY FIRST No accounts, no tracking, no intermediary servers. Your API key is stored only on your device and never synced. Your selected text goes directly from your browser to the AI provider you configured, only when you trigger an action, and nowhere else. SUPPORT Questions or issues: https://github.com/dmarafetti/ai-writer-extension/issues