Yes, all ZapFile tools are completely free with no hidden costs or subscriptions.

Absolutely. All processing happens directly in your browser. Your files are never uploaded to any server.

Do I need to create an account?

No. ZapFile requires no registration, login, or account creation.

Does this tool work offline?

Most tools work offline after the first load. ZapFile is a Progressive Web App you can install.

Yes! All tools are fully responsive and work on mobile devices.

Convert length, weight, temperature, volume, area, speed, data, CSS units and more

mmmillimeterscmcentimetersmmeterskmkilometersininchesftfeetydyardsmimilesnmi

Type in any field; all others update instantly. Decimal comma or point both work.

Runs on your device, not our servers

This page uses browser APIs (Canvas, WebAssembly, workers, etc.) so your files stay on your machine.

Processing happens in this tab — close the tab and the session ends.
No ZapFile account is required and we do not store your uploads (there are none).
Download only what you choose; nothing is sent to us for “cloud processing.”
Verify it yourself: DevTools → Network while using a tool — you should not see your file bytes uploaded to ZapFile.
Add ZapFile to your home screen for a faster app shell and offline access to cached pages (tools still need a capable browser).