How to Compress Images Without Uploading Them

Many online image tools upload your files to a server to process them. There is a better way: compress images entirely inside your browser.

Why it matters

• Privacy: sensitive images (IDs, contracts, unreleased work) never leave your device.
• Speed: no upload/download round trip, so results appear instantly.
• Offline: once loaded, the tool keeps working without a connection.

How it works

Modern browsers can decode images to raw pixels and run compression codecs compiled to WebAssembly — the same libraries desktop tools use. The heavy work runs in background threads so the page stays responsive.

Is it as good as server tools?

Yes. The codecs are the same, so quality and file size match server-side tools. The only limit is your device's CPU, which handles typical batches easily.

Scrunch is built this way: your images are processed locally and never uploaded. Convert as many as you like with full privacy.