Answer
Why does my photo show no EXIF data at all?
Almost always because the file has already been through something that removed it — a platform upload, a screenshot, a chat app or an export.
Updated
The most common explanation is that you are not looking at the original. If the image was downloaded from a social network, saved out of a chat app, or copied from a web page, it has already been re-encoded at least once, and re-encoding discards the metadata block. The file you have is a descendant of the original, several generations removed.
Screenshots are the second common case, and a subtle one, because a screenshot of a photo looks like the photo. It is a new file that was never near a camera, so there was no EXIF to carry over in the first place.
Some formats simply carry less by convention. PNG rarely holds GPS, because a PNG is usually a screenshot or an export rather than a camera original — but PNG is also where AI image tools write prompts and seeds, so an apparently bare PNG can still be carrying a great deal of text. GIF has very little room for metadata by design.
It is also worth checking that your viewer is looking in the right places. Metadata is not one block: EXIF, IPTC, XMP, the ICC colour profile and C2PA credentials are stored separately, in different structures, and plenty of tools read only the first of those. A file that reports "no EXIF" may still be carrying an XMP packet or a content credential. The viewer here reads all of them.
And occasionally the answer is that nothing is wrong — a camera with location services disabled and a manufacturer that writes a minimal block produces a genuinely sparse file.
More on this: EXIF viewer.
Terms used here: EXIF, IPTC, XMP, C2PA.