LanTransfer is a cross-platform local-network file and text transfer tool designed for seamless sharing of files and notes between devices on the same network. It features a browser-based interface, QR-code connection, and operates without cloud dependency.
Key Features:
Cross-Platform Support: Works across Windows, macOS, Linux, Android, and iOS.
QR-Code Connection: Quickly connect devices via scanned QR codes for easy setup.
Browser-Based UI: No installation needed; use any modern browser to transfer files and text.
HTTP-Based Transfers: Secure file sharing using HTTP protocol without the need for internet access.
Chat-Style Interface: User-friendly design optimized for phones, tablets, and desktops.
Safe File Handling: Includes streaming saves and protection against path traversal.
Target Audience and Benefits:
Ideal for individuals and teams seeking a secure, reliable method to transfer files locally. LanTransfer offers the benefit of ease of use with cross-platform compatibility, ensuring efficient and safe file sharing without internet dependency.
Available via Winget, install LanTransfer quickly using "install LanTransfer via winget" or deploy it through the winget command line for automated setup.
LanTransfer is a cross-platform LAN file and text transfer tool powered by .NET and a browser-based UI. Run lantransfer on one device, then scan its local QR code from another phone, tablet, or computer on the same network.
Features
Browser-based LAN file upload/download and plain-text notes
Local QR connection dialog with multi-adapter address selection
Cross-platform host named lantransfer
ASP.NET Core Kestrel receiver using HTTP by default for LAN access
Static HTML/CSS/JavaScript UI with no frontend build system
Chat-style file transfer interface for phones, tablets, and desktops
Streaming file saves with temporary .uploading files
Safe file-name handling, path traversal protection, and readable duplicate names
Lightweight English and Simplified Chinese web UI localization
Default-browser launch after startup
Native LanTransfer icon with an Open/Exit tray menu and no console window on Windows; unchanged console behavior on macOS/Linux
Screenshot
Platform Support
Receiver:
Windows, macOS, or Linux with .NET 10
Sender:
Any modern browser on Windows, macOS, Linux, Android, or iOS
Network:
Devices must be on the same local network unless you configure VPN, tunneling, or routing yourself.
Quick Start
dotnet run --project src/LanTransfer.Host
LanTransfer listens on http://0.0.0.0:8765 and opens the local page in your default browser. Use Connect new device in the page menu to show a QR code for each detected LAN address.
Open one of these URLs:
Same device: http://localhost:8765
Another device on the LAN: http://:8765
The first version intentionally uses HTTP on the local network. It does not require trusting an ASP.NET Core development HTTPS certificate.
If AccessToken is configured, protected API calls must include X-LanTransfer-Token or ?token=....
When StorageDirectory is null, LanTransfer stores received files under the current user's local application-data directory (%LOCALAPPDATA%\LanTransfer\uploads on Windows). Set an absolute or app-relative path to override it. Keeping the default outside the executable directory makes package upgrades and uninstall safe for user files.
Environment variables can override configuration values by using the LanTransfer__ prefix, for example:
LanTransfer__Port=9000 dotnet run --project src/LanTransfer.Host
On PowerShell:
$env:LanTransfer__Port = "9000"
dotnet run --project src/LanTransfer.Host
API Overview
GET /api/health returns service status and device name.
GET /api/connect returns usable LAN connection URLs.
GET /api/connect/qr?url=... returns a locally generated SVG QR code.
GET /api/messages lists plain-text notes.
POST /api/messages sends a plain-text note.
POST /api/files/upload uploads one multipart file field named file.
GET /api/files lists received files.
GET /api/files/{fileName} downloads a received file.
Error responses use stable errorCode values such as file_too_large, invalid_file_name, invalid_message, unauthorized, upload_failed, and network_error.
Build from Source
dotnet build LanTransfer.sln
dotnet test LanTransfer.sln
Use the release script to test, tag, and push a new version:
.\scripts\release.ps1 0.1.0
The script creates and pushes a v0.1.0 tag. GitHub Actions then creates a GitHub Release, publishes self-contained builds, and uploads assets for Windows x64, Linux x64/ARM64, and macOS x64/ARM64.
To preview the checks without creating a tag, run:
