Grammarly, but yours. Open source.
WriteWise is an AI writing assistant that lives in your browser and works everywhere you type — email, docs, social media, PRs, you name it. Fix grammar, rewrite sentences, change tone, or generate entire emails from a description. All of it runs through your own API key, straight from your browser to the AI provider. No servers, no accounts, no data leaving your machine except to the provider you chose.
- Grammar & style check — automatic underlines (spelling, grammar, clarity, style) as you type in any text field or rich editor
- Quick Actions toolbar — select any text on any page, get a floating toolbar with 8 actions: Fix Grammar, Rewrite, Improve, Formal, Casual, Shorter, Expand, and Write (generate from scratch)
- Inline analysis panel — click the badge icon to see issues one at a time with accept/dismiss, or apply all fixes at once. Toggle auto-analysis on/off in Settings.
- Write from scratch — choose "Write" from any quick action toolbar to get a small dialog where you describe what you want (email, tweet, message, etc.) and the AI generates it on the spot
- History — every fix you accept is saved, grouped by day, so you never lose track of what changed
- Usage tracking — requests, tokens, and estimated cost, with a built-in pricing table for 26+ models
- Dark, calm UI — warm cream and forest green, because your editor shouldn't look like a spaceship
- Install the extension
- Grab an API key from OpenAI, Anthropic, or OpenRouter (or all three)
- Paste it in the settings — it stays in
chrome.storage.local, never sent anywhere else - Click any text field on any website and start typing
The extension detects editable fields, analyzes your text locally for issues, then sends only the relevant snippet to the AI when you accept a fix or use a Quick Action. Your API key never touches a WriteWise backend — because there isn't one.
┌─ Your Browser ────────────────────────────────────┐
│ │
│ content.js ──→ chrome.runtime.sendMessage │
│ detects (AI_REQUEST) │
│ text areas │
│ │ │
│ ▼ │
│ background.js ──→ OpenAI / Anthropic / │
│ proxies OpenRouter API │
│ request (your key) │
│ │
└── No WriteWise servers. Ever. ────────────────────┘
| Provider | Models | Notes |
|---|---|---|
| OpenAI | GPT-4o, GPT-4o-mini, GPT-4, GPT-3.5, O1, O3-mini | Bring your own API key |
| Anthropic | Claude Opus 4, Sonnet 4, 3.5 Sonnet, 3.5 Haiku, 3 Haiku | Bring your own API key |
| OpenRouter | 300+ models (Gemini, Llama, DeepSeek, Mistral, Qwen, etc.) | One API key, any model |
Pick whichever provider you already use. For most users, OpenRouter + DeepSeek V4 Flash is the sweet spot — $0.14/M tokens, free 5M token grant, and 300+ models available with one key.
| Grammarly Premium | WriteWise + DeepSeek V4 Flash | |
|---|---|---|
| Monthly cost | $12/month (annual) or $30/month | ~$0.05–$0.30 for normal use |
| Per check | Included in subscription | ~$0.00006 (≈190k checks per $12) |
| Free usage | None | 5M free tokens (~16k checks) |
| Model choice | Grammarly only | 300+ models, swap anytime |
| Data privacy | Sent to Grammarly servers | Straight to your chosen provider |
| Offline? | No | Yes (local analysis, no server) |
This is the whole backend:
{ "backend": null }- No database. Your fixes are stored in
chrome.storage.local— a JSON file in your browser profile. - No analytics. No telemetry, no tracking pixels, no "crash reports."
- No accounts. No signup, no login, no "forgot password."
- No API proxy. Your key goes from
background.jsstraight to the provider's REST API. - No surprises. The code is right here. Read it. Audit it. Fork it.
| Action | What it does |
|---|---|
| Fix Grammar | Fix all grammar, spelling, and punctuation errors |
| Rewrite | Rewrite for better clarity and flow |
| Improve | Improve word choice and overall quality |
| Formal | Make more formal and professional |
| Casual | Make more casual and conversational |
| Shorter | Make more concise without losing meaning |
| Expand | Expand with more detail and depth |
| Write | Generate new content from a description (e.g. "write a polite follow-up email") |
[Link pending — once published]
git clone https://github.com/Yash094/WriteWise.git
cd writewise- Open
chrome://extensions - Enable Developer mode (toggle top-right)
- Click Load unpacked
- Select the
writewisefolder
That's it. No build step, no npm install, no transpilation. It's vanilla JS.
Full installation guide with screenshots → INSTALL.md
npm run build
# Creates dist/writewise.zipClick the extension icon → Open Settings to configure:
- OpenRouter (Recommended) — first tab in settings. One key for 300+ models.
- API Key — paste your key from OpenRouter, OpenAI, or Anthropic
- Model — pick from the live model list. DeepSeek V4 Flash is recommended for best value
- Analysis — toggle auto-analyze on/off. When off, analysis only runs when you click the badge icon
- Usage — see how many requests you've made and estimated cost
- History — browse all accepted fixes, grouped by day
Because every popular option either:
- Ships your text to a third-party server you don't control
- Costs $12–$30/month whether you use it or not
- Can't be audited, forked, or modified
WriteWise is the opposite. You pick the model, you pick the provider, you pay only for what you use (or nothing if you're on a free tier). The code is MIT — use it, change it, redistribute it.
This project is open source but does not yet have a formal license file. A MIT license will be added shortly. Until then, assume all rights reserved — but the intent is permissive open source. Contributions welcome.
PRs are welcome. The codebase is vanilla JS with no build step — just content.js, background.js, and the options/ and popup/ directories. The architecture is simple by design.
content.js— all UI and page interaction (analysis, toolbar, panel, toast)background.js— service worker (AI API calls, usage tracking, pricing)options/— full settings page (API keys, model picker, history, about)popup/— extension toolbar popup (status summary)
Your API key is stored in chrome.storage.local — it never leaves your browser except to authenticate with the provider you chose. There is no WriteWise server, no analytics, no tracking. The extension works entirely client-side.
Made with ☕ and zero venture capital.
WriteWise · Open source · Yours.