Are online file converters safe? What happens to your files

A typical converter copies your file to its servers, converts it there and keeps it for a while so you can download the result. Reputable services delete files after a few hours, but you are trusting their word, their security, and every company they use for hosting and storage.

Files that sit on a server, even briefly, can be exposed by a breach, a misconfigured storage bucket or an over-broad internal access policy. None of this is visible to you.

Photos usually carry metadata: the exact GPS location where they were taken, the date and time, and the phone model. Documents can contain author names and edit history. When you upload a file, all of that goes with it.

When Localvert re-encodes an image, that metadata is not carried over to the new file, so the converted photo no longer reveals where it was taken.

Modern browsers can do the heavy lifting themselves. Image formats are decoded and re-encoded with the browser's own graphics engine, and formats browsers don't support natively — HEIC, video, audio — are handled by open-source libraries compiled to WebAssembly that run on your own processor.

The site downloads the program to you; your file never goes the other way.

You don't have to take anyone's word for it. Open your browser's developer tools (F12, or Ctrl+Shift+I), switch to the Network tab, and convert a file. On an upload-based service you'll see a large outgoing request carrying your file. On Localvert there is none.

Be especially careful with identity documents, bank statements, contracts, medical records, and photos of your children or your home. For these, prefer tools that process locally — either an app on your computer or an in-browser converter — over services that upload.