EXIF Viewer

What EXIF actually is

EXIF — Exchangeable Image File Format — is a convention for storing structured metadata inside image files, principally JPEG and TIFF. It was designed so cameras could record the circumstances of a photograph: shutter speed, aperture, ISO, focal length, white balance, the make and model of the body and lens. Over time the specification accumulated space for much more, including a timestamp, a GPS fix, the name of the software that last touched the file, an author, a copyright notice, and vendor-specific "maker note" blocks whose contents are undocumented and differ between manufacturers. Because it travels inside the file rather than alongside it, the metadata follows the image wherever it goes.

Why location is the tag that causes trouble

A GPS fix in a photograph is precise, durable and invisible. It is not displayed by image viewers, it survives copying and emailing, and most people have no idea it is there. Coordinates accurate to a few metres identify a specific building, and a set of photographs identifies a pattern of movement. Large social platforms generally remove EXIF when an image is uploaded, which has created a widespread assumption that sharing is safe — but that protection is a property of those specific services, not of the file. Sending the same photograph as an email attachment, posting it to a forum, or putting it in a shared drive preserves everything. This tool flags a location fix prominently for exactly that reason: it is the one tag whose disclosure can have consequences beyond the digital.

Removing metadata reliably

There are two ways to strip metadata. The first is to parse the container, find the metadata segments, and write the file back without them. This preserves the original compressed pixel data exactly, but its completeness depends entirely on the parser recognising every segment that might carry data — and vendor-specific blocks are, by definition, not fully documented. A tool taking this approach can leave data behind while reporting success. The second approach, used here, is to decode the image to raw pixels and encode a new file from those. Nothing but the pixels survives, because nothing else is carried across; the metadata is not removed so much as never created. The cost is a generation of lossy re-encoding on formats like JPEG. That trade — a small, usually imperceptible quality loss in exchange for a removal you can actually rely on — is the right one when the purpose is privacy rather than housekeeping.