ShareDrop — Peer-to-Peer File Sharing in the Browser via WebRTC

Introduction

ShareDrop is an open-source, browser-based file sharing tool that sends files directly between devices using WebRTC peer-to-peer connections. No file ever touches a server, making transfers fast and private. Devices on the same local network discover each other automatically.

What ShareDrop Does

• Transfers files directly between browsers using WebRTC data channels with no server upload
• Auto-discovers devices on the same local network for AirDrop-like convenience
• Supports cross-network sharing via unique room URLs for transferring files over the internet
• Works on any modern browser including mobile Safari and Chrome without installing an app
• Keeps all data client-side with end-to-end encrypted WebRTC connections

Architecture Overview

ShareDrop uses a lightweight signaling server to help peers discover each other and negotiate WebRTC connections. Once the connection is established, files flow directly between browsers over encrypted DTLS/SCTP data channels. The signaling server sees only connection metadata, never file contents. For local network discovery, the app leverages the same signaling server with network-aware room assignment.

Self-Hosting & Configuration

• Clone the repository and run npm install followed by npm start for local development
• Deploy to any static hosting platform since the client is a single-page application
• Configure the signaling server URL in the environment to point to your own PeerJS or custom signaling backend
• Set up TURN servers for reliable transfers between devices behind restrictive NATs or firewalls
• Optionally use the hosted version at sharedrop.io with no setup required

Key Features

• Zero-upload architecture: files transfer peer-to-peer and never leave the users' devices
• No registration, no accounts, no file size limits imposed by the application
• Responsive design works on desktop and mobile browsers equally
• Local network auto-discovery groups nearby devices for instant sharing
• Progressive Web App support allows adding ShareDrop to the home screen

Comparison with Similar Tools

• AirDrop — Apple ecosystem only; ShareDrop works on any device with a modern browser
• LocalSend — native app requiring installation; ShareDrop runs entirely in the browser
• PairDrop — fork of Snapdrop with additional features; ShareDrop is the original WebRTC file sharing concept
• Send (Firefox Send) — uploads to a server then shares a link; ShareDrop transfers directly peer-to-peer
• croc — CLI tool; ShareDrop provides a graphical browser interface with no installation

FAQ

Q: Is there a file size limit? A: ShareDrop itself imposes no limit. Practical limits depend on browser memory and WebRTC data channel stability for very large files.

Q: Do files pass through any server? A: No. The signaling server only helps establish the WebRTC connection. File data flows directly between browsers.

Q: Does it work across different networks? A: Yes. Share a room link to connect devices on different networks. A TURN server may be needed if both peers are behind strict NATs.

Q: Can I share with multiple people at once? A: You can share with multiple peers in the same room, but each transfer is a separate peer-to-peer connection.

Sources

• https://github.com/szimek/sharedrop
• https://www.sharedrop.io/