What is EXIF metadata?

EXIF stands for Exchangeable Image File Format. It is a convention, dating from the mid-1990s, for writing structured information into an image file alongside the pixels. Your camera fills it in automatically. Your phone fills in more. Editing software adds its own layers on top.

None of it is visible when you look at the picture, and all of it travels with the file.

The three standards you will meet

People say "EXIF" as shorthand for all embedded metadata, but there are really three systems, and they coexist in the same file:

• EXIF — written by the camera. Make, model, body and lens serial numbers, exposure settings, orientation, timestamps, and GPS coordinates if location was enabled.
• IPTC — a press and publishing standard. Caption, credit, byline, copyright, contact details, keywords. Filled in by photo editors and asset management systems.
• XMP — Adobe's XML-based format. Everything above, plus an edit history recording which applications touched the file and when, and a document identifier that persists across saves.

A photo that has been through a phone and then a desktop editor typically carries all three.

What it actually reveals

Ranked by how much a stranger can learn from it:

1. GPS coordinates. Latitude, longitude and usually altitude, accurate to a few metres. Often the compass bearing too. This does not tell someone your city; it tells them which building, and roughly which floor.
2. Serial numbers. Camera bodies and lenses have unique identifiers, and they are written into every file. That is a durable link between every photo you have taken with that equipment, even across accounts with no other connection.
3. The embedded thumbnail. This one surprises people. Cameras store a small preview inside the EXIF block. Some editors update it when you edit; some do not. If you cropped something out of a photo and the thumbnail was not regenerated, the original framing is still in the file.
4. Names and copyright. Editing software often auto-fills the Artist and Copyright fields with your real name, once, in settings you have long forgotten.
5. Timestamps. Any single one is meaningless. A set of them describes when you sleep, when you commute, and when your home is empty.

Where it is stored

In JPEG, metadata sits in application marker segments before the compressed image data. In PNG it lives in named chunks. In HEIC, AVIF and MP4 it is stored as items or boxes inside an ISO Base Media container. TIFF is the odd one out: there, the metadata directory is the file's structure.

This is why removal has to be format-specific, and why a tool that only understands JPEG will quietly do nothing useful to your HEIC. The format pages cover each one.

Why it is not simply bad

Metadata is genuinely useful. Photographers rely on exposure data to learn from their own work. Copyright fields support licensing claims. Orientation flags stop your photos appearing sideways, and colour profiles keep colours consistent between screens.

So the sensible position is not "delete everything". It is: know what is in there, remove what identifies you, and keep what makes the file work. That is why rotation and colour profile are preserved by default here, while location, serial numbers and names are not.

The common misconception

Many people assume social networks handle this for them. Mostly they do strip metadata — from the copy other users can download. Your original file, coordinates included, still reached their servers, and anything you send by email, messaging app file mode, or shared drive is untouched by any of it. There is aplatform-by-platform breakdown if you want the detail.

The reliable habit is to strip locally, before the file leaves your device.