Elevate your notes using advanced AI models and BYOK security. A privacy-first web app that transforms audio recordings into structured academic notes and professional PDF edit-export capabilities. Built with Astro, React, and TypeScript for a blazing fast, zero-latency experience.
BYOK Edition: Bring Your Own Key. No subscriptions, no backend data storage, and 100% client-side processing for maximum privacy.
Try the application immediately: compendium-notes.vercel.app
The web application runs entirely in your browser using client-side processing (your audio and keys never touch a backend server).
Security Note:
- The web version is fully secure and safe to use with your API Keys.
- However, if you prefer maximum isolation or strict corporate compliance, you can run the application locally (
localhost) using the installation steps below.
- 100% Free & Unlimited - No paywalls, no subscriptions. Bring your own free API keys and process as many hours as you need.
- Dual AI Engine - Choose between Groq (Extreme Speed) and Gemini (Massive Context & Multimodal).
- Smart Audio Chunking - Automatically splits long audio files (e.g., 2+ hour lectures) into optimal segments using FFmpeg, avoiding API timeouts and enabling infinite transcription length for Gemini.
- Privacy-First Architecture - Keys and data stored exclusively in
localStorage. Direct Browser-to-API communication. Your data never touches our servers. - Intelligent Transcription - Uses Whisper v3 Turbo (via Groq) or Gemini 3.1 Flash Lite for lightning-fast, highly accurate audio-to-text.
- AI-Powered Organization - Automatically extracts topics, key concepts, and generates structured Markdown notes using intelligent prompting via Gemini 3 Flash.
- Premium Export - Download your structured notes directly into Minimalist, Academic, or Cornell PDF styles.
- Built-in Audio Player - Review your recordings while reading or editing the generated notes, with synchronized progress tracking.
- Dark & Light Mode - Full support for both themes with automatic system preference detection.
- Multi-Language - Native support for English and Spanish.
- Frontend: Astro (Static Shell) + React (Interactive App)
- Styling: Vanilla CSS + Tailwind + Framer Motion
- State Management: Zustand + Dexie.js (IndexedDB for persistent sessions)
- Audio Processing: Web Audio API +
@ffmpeg/ffmpeg(WebAssembly) - AI Integration: Direct REST API calls to Groq & Google AI Studio
Real-world processing performance for a 1-hour lecture (~50MB audio):
| Provider | Model | Speed | Cost | Best For |
|---|---|---|---|---|
| Groq | Whisper v3 + Llama 3 | ~15-30 seconds | Free | Fast drafts & short meetings |
| Gemini | 3.1 Flash Lite + 3 Flash | ~30-45 seconds | Free | Long seminars, extreme accuracy |
The Pipeline Flow:
- Audio Compression: Large files are automatically compressed locally using Web Audio API down to 16kHz mono (reducing 100MB files to ~10MB).
- Intelligent Chunking: If using Gemini and the audio exceeds 45 minutes, it is seamlessly split into 30-minute chunks using FFmpeg WebAssembly.
- Parallel Transcription: The chunks are sent directly from your browser to the AI provider.
- Markdown Organization: The raw transcript is passed back to the AI to extract a title, format into Markdown sections, and summarize.
- Interactive Editor: Review the transcript, edit the markdown, and export to PDF.
graph TD
User["User Browser"]
subgraph "Client Side (Your Device)"
Upload["Audio/Video File"]
Store["LocalStorage (Keys)"]
App["Compendium Notes App"]
AudioAPI["Web Audio API (Compression)"]
FFmpeg["FFmpeg WebAssembly (Chunking)"]
end
subgraph "External AI APIs"
Groq["Groq API (Whisper/Llama)"]
Gemini["Google API (Gemini 3.1 Flash Lite + 3 Flash)"]
end
User --> Upload
Upload --> App
Store --> App
App --> AudioAPI
AudioAPI -- "If > 45 mins & Gemini" --> FFmpeg
AudioAPI -- "Otherwise" --> APIs
FFmpeg -- "Multiple Parallel Chunks" --> Gemini
APIs{"API Router"}
APIs -- "Direct HTTPS" --> Groq
APIs -- "Direct HTTPS" --> Gemini
Groq -- "Transcription & Notes" --> App
Gemini -- "Transcription & Notes" --> App
App --> Result["Formatted PDF/Notes/Markdown"]
- Node.js 18+
- NPM or PNPM
-
Clone the repository:
git clone https://github.com/ForcexDev/compendium-notes.git cd compendium-notes -
Install dependencies:
npm install
-
Launch the development server:
npm run dev
-
Access the app at
http://localhost:4321
No complex setup required. The application works out-of-the-box.
To use the application, you will need a free API Key from:
- Groq: console.groq.com
- Google Gemini: aistudio.google.com
Enter them in the application settings (gear icon).
- University Students - Record lectures and instantly get Cornell-style study notes.
- Professionals - Transcribe meetings and generate executive summaries and action items.
- Researchers - Process interviews and oral histories into searchable text.
- Content Creators - Convert voice memos into blog posts or structured scripts.
- Ensure your key has no extra spaces.
- Verify you have selected the correct provider matching your key.
- Groq: Free tier has strict per-minute limits. If you hit them, wait a minute or switch provider.
- Gemini: If you see "Limit 0" or 429 immediately, you likely need to link a Billing Account (credit card) in Google AI Studio.
- Important: The "Pay-as-you-go" plan often includes a massive Free Tier (or effectively Unlimited for Gemini 3.1 Flash Lite/3 Flash, as confirmed in testing) but requires identity verification.
- Without billing, you are on a restricted "Free of Charge" tier which may be lower.
Contributions are welcome! Please open an issue to discuss major changes before submitting a pull request.
- Fork the Project
- Create your Feature Branch (
git checkout -b feature/AmazingFeature) - Commit your Changes (
git commit -m 'Add some AmazingFeature') - Push to the Branch (
git push origin feature/AmazingFeature) - Open a Pull Request
This project is licensed under the MIT License.
Developed by ForcexDev