Putty to OpenSSH converter

PuTTY to OpenSSH Converter

A web application that converts PuTTY Private Key (PPK) files to OpenSSH format (PEM) without requiring local installation of PuTTY tools.

Why I Made This

As someone who exclusively uses OpenSSH keys, I found it annoying to install PuTTY just to convert keys when collaborating with others who use PuTTY. This web app solves that problem by:

• Providing a simple web interface for converting keys
• Handling the conversion process on the server side
• Returning both private and public keys in a zip file
• Automatically deleting all files after conversion for security

Features

• Instant conversion from PPK to OpenSSH format
• Returns both private and public keys
• Secure by design - all files are deleted after conversion
• Responsive UI that works on desktop and mobile
• Containerized with Docker for easy deployment

Technology Stack

• Backend: Bun with Hono framework
• Frontend: React with TypeScript, Vite, and shadcn/ui
• Conversion: Uses puttygen CLI tool
• Container: Docker and Docker Compose
• Web Server: Caddy (for production)

Security

• All files (both uploaded and converted) are deleted from the server immediately after conversion
• No files are stored long-term
• Conversion happens server-side using the puttygen CLI tool
• File size limits to prevent abuse