# Quillzy

> Quillzy is a free, privacy-first Chrome extension that uses AI to help users write better LinkedIn content. It supports five modes: Repost, New Post, Comment, DM Reply, and Connection Note. Users can choose from three AI providers: Browser AI (free, offline, on-device), Google Gemini (free tier available), and OpenAI GPT (premium). Rated 5.0 stars on the Chrome Web Store.

Website: https://quillzy.com
Chrome Web Store: https://chromewebstore.google.com/detail/khfikcfcjamhalghcbgnhldaenlccfpb
GitHub: https://github.com/yogendrasinghx/Quillzy

## About

Quillzy is an AI-powered LinkedIn writing assistant Chrome extension. It injects a smart toolbar directly into LinkedIn's editor for posts, reposts, comments, DM replies, and connection notes, so users can generate engaging, professional content with one click.

The extension is completely free to use with Browser AI mode, which runs Gemini Nano entirely on the user's device. No API key is needed, it works offline, and no data ever leaves the browser. For users who want cloud-powered AI, Quillzy also supports Google Gemini (with a free tier) and OpenAI GPT.

Quillzy collects zero user data. No tracking, no analytics, no personal information. API keys are stored locally in Chrome's secure storage.

## Five Modes

### Repost Mode
Generate compelling commentary when sharing someone else's LinkedIn post. AI reads the original post content and images, then writes engaging commentary. Supports 17 tones (Professional, Casual, Witty, Inspirational, Storytelling, etc.) plus custom tones. Image-aware AI analyzes post images for richer context.

### New Post Mode
Write a rough draft in the LinkedIn editor, then let AI rephrase and enhance it into polished content while preserving the user's voice. Supports word count control and custom system prompts.

### Comment Mode
Generate short, context-aware comments (max 300 characters) on LinkedIn feed posts, company pages, profile feeds, and activity pages. AI reads the post context and writes a relevant comment. The compact toolbar appears inline with the comment editor.

### DM Reply Mode
AI reads the last few messages in a LinkedIn conversation and generates a natural, conversational reply (max 500 characters). Works in the messaging overlay and full messaging page. Supports draft context if the user has started typing.

### Connection Note Mode
Generate personalized connection request notes (max 200 characters) when sending invitations on LinkedIn. AI reads the recipient's profile name and context to craft a warm, genuine note.

## AI Providers

### Browser AI (Recommended, Free)
- Uses Gemini Nano, a small AI model built into Chrome
- Runs entirely on the user's device (no cloud, no API key)
- Works offline after a one-time model download (~1-2 GB)
- Requires Chrome 138+, 22 GB storage, 4 GB+ VRAM or 16 GB RAM
- Completely free forever
- Zero data leaves the browser

### Google Gemini
- Cloud API with free tier available
- Models: Gemini 2.5 Flash, Gemini 2.5 Pro, Gemini 2.0 Flash
- Supports image-aware commentary (sends post images to Gemini)
- Requires a Google AI Studio API key
- Most users spend under $1/month

### OpenAI GPT
- Premium cloud API
- Models: GPT-5 Nano, GPT-4o, GPT-4.1, GPT-5 Pro
- Supports image-aware commentary
- Requires an OpenAI Platform API key
- Pay-per-use pricing

### Free Tier (No API Key)
Users can also use ChatGPT, Claude, or Gemini web interfaces directly. Quillzy builds the prompt and auto-fills it in a new tab. No API key or account needed for basic use.

## Key Features

- **17 Built-in Tones**: Professional, Casual, Witty, Inspirational, Storytelling, Analytical, Supportive, Bold, Humorous, Empathetic, Motivational, Curious, Grateful, Visionary, Reflective, Direct, Custom
- **Image-Aware AI**: Extracts images from LinkedIn posts and sends them to AI for visually-aware commentary (Gemini and OpenAI only)
- **Max Word Count Control**: Fine-tune output length per mode
- **Custom System Prompts**: Create and manage custom prompt templates
- **Dark Mode**: Automatic theme detection with manual toggle
- **Model Selection**: Pick from the latest AI models across all providers
- **Streaming Responses**: AI output streams in real-time as it's generated
- **Privacy-First**: API keys stored locally in Chrome's encrypted storage, never exposed

## Privacy & Security

- API keys stored in Chrome's built-in sync storage, never exposed in URLs
- API calls go directly from the browser to the AI provider (Google/OpenAI)
- Quillzy does not collect, store, or transmit any personal data
- Browser AI processes everything on-device; data never leaves the browser
- Zero analytics, telemetry, or usage monitoring
- No third-party tracking scripts
- Content Security Policy (CSP) configured in the extension manifest
- Image fetching restricted to media.licdn.com host permission only

Privacy Policy: https://quillzy.com/privacy
Terms of Service: https://quillzy.com/terms

## How It Works

1. **Install**: Add Quillzy to Chrome in one click from the Chrome Web Store. No sign-up required.
2. **Configure**: Choose your AI provider. Browser AI is free and works offline. Or add your own Gemini/OpenAI API key.
3. **Write**: Open LinkedIn and start creating. Quillzy's AI toolbar appears automatically wherever you can write (post editor, comment box, DM compose, connection modal).

## Tech Stack

- Chrome Extension (Manifest V3) built with WXT framework
- React 19 + TypeScript (strict mode)
- Tailwind CSS 4 with shadcn/ui components
- Zod for runtime validation
- Zustand for state management
- Vitest for testing
- Landing page: Next.js 15 (static export) on Cloudflare Pages

## FAQ

**Is Quillzy free?**
Yes! Browser AI mode is completely free. It runs on your device with no API key needed. You can also use the Free Tier mode with ChatGPT, Claude, or Gemini web at no cost. API mode (Gemini/OpenAI) uses your own API key, and most users spend under $1/month.

**Does Quillzy collect my data?**
No. Quillzy collects zero user data. No tracking, no analytics, no personal information. API keys are stored locally in Chrome's secure storage. With Browser AI, everything is processed on-device.

**What is Browser AI?**
Browser AI uses Gemini Nano, a small AI model built into Chrome that runs entirely on your device. It requires a one-time model download and works offline after that. No API key needed, completely free.

**Which AI provider should I choose?**
Start with Browser AI. It's free, private, and works offline. If you want higher quality or image-aware commentary, try Google Gemini (has a free tier). OpenAI GPT offers premium quality for power users.

**Does it work on all LinkedIn pages?**
Yes! Quillzy works on the LinkedIn feed, company pages, profile pages, activity pages, messaging, and connection request modals. The AI toolbar appears automatically wherever you can write on LinkedIn.

**Can I customize the AI output?**
Absolutely. Choose from 17 built-in tones (Professional, Casual, Witty, Inspirational, etc.) or create your own custom tone. You can also set max word counts and write custom system prompts.

**Are my API keys safe?**
Yes. API keys are stored in Chrome's built-in sync storage, never exposed in URLs or sent to any third party. API calls go directly from your browser to the AI provider (Google/OpenAI). Quillzy never sees your keys.

## Author

Built by Yogendra Singh — Founder of Quillzy, making LinkedIn engagement effortless.
Website: https://yogendrasingh.in
LinkedIn: https://www.linkedin.com/in/yogendrasinghx/
GitHub: https://github.com/yogendrasinghx