How Image Metadata Works — and What Removing It Actually Does
EXIF, what cameras and phones store, what a browser re-encode can and cannot strip, and how to verify the result.
EXIF is data embedded in a JPEG by the camera or phone: camera make and model, date and time, orientation, and sometimes GPS coordinates. It travels with the file unless something strips it.
Phones and cameras add this data automatically. Screenshots and images saved by some apps carry little or none, which is why the Metadata Viewer sometimes reports "No EXIF data found" — that is a real result, not a failure.
Removing metadata on this site works by re-encoding the image through the browser Canvas. The new file contains the pixels but not the original EXIF block. That covers standard EXIF in practice.
What re-encoding does not guarantee: proprietary metadata blocks that a browser cannot see, and anything embedded in the image pixels themselves (such as a visible watermark). For highly sensitive material, verify the output with the Metadata Viewer and consider whether the image should be shared at all.
A final caution: removing metadata does not make a photo anonymous. People, places, number plates and reflections in the photo itself can still identify a subject.