I Built a File Converter That Never Uploads Your Files — Here's How

Most online file converters have a dirty secret: they upload your files to their servers, process them, and send them back. Even the ones that promise "files are deleted after 1 hour" — you're still trusting a third party with your passport photos, medical records, and personal documents. I wanted to fix this. So I built OneWeeb — a file converter that runs 100% in your browser . Your files never leave your device. Ever. Here's how it works under the hood. The Problem With Server-Side Converters When you use a typical online converter: Your Device → Upload → Their Server → Process → Download → Your Device Your file travels across the internet twice. It sits on someone else's server. You have no control over what happens to it. With client-side processing: Your Device → Process → Your Device That's it. No network requests. No server. No trust required. The Tech Stack Everything runs on vanilla JavaScript and browser APIs. No frameworks, no build tools. Here's what powers each conversion