Privacy

Why In-Browser Tools Keep Your Files Private

Most "free" converters upload your files to a server. Here is how client-side processing works and why it matters.

Why In-Browser Tools Keep Your Files Private
On this page
  1. The problem with upload-based tools
  2. How client-side processing works
  3. How to verify it yourself

The problem with upload-based tools

Many online converters send your file to a remote server, process it there and send it back. That means a copy of your private photo, contract or ID may sit on a server you know nothing about.

How client-side processing works

Modern browsers can run powerful code through JavaScript, Canvas and WebAssembly. ToolCMB loads the tool once and then processes your file entirely on your device.

How to verify it yourself

  1. Open the tool and press F12 to open DevTools.
  2. Go to the Network tab.
  3. Process a file — you will see no upload request.

Privacy should not be a premium feature. That is why every ToolCMB tool is private by default.

Written by ToolCMB Team

We build fast, free and private browser tools — and write practical guides on how to use them.

How to Convert Files Without Uploading Them

Convert images, PDFs, JSON data and other files directly in your browser without uploading them to a remote server. Learn how browser-based file conversion works, when it is useful, and how to convert files more privately with ToolCMB.