How Do I Check That My Photo Dates Are Actually Fixed?
Do not trust a progress bar with your family photos. Here is how to verify the dates really landed, on any platform.
Verify on a handful of photos you know well before you trust a whole run. Pick a picture where you remember the actual day.
On Windows, right-click the photo, choose Properties, then Details, and look at "Date taken". That is the EXIF field. If it matches and "Date modified" matches too, both halves are correct. On a Mac, open the photo in Preview, then Tools, then Show Inspector, and check the Exif tab. Finder's Get Info shows the file dates. On any platform, exiftool -DateTimeOriginal -CreateDate photo.jpg prints the truth with no interpretation.
Check three kinds of file, not one: a normal camera photo, a screenshot, and something from WhatsApp or a chat app. Those last two are the ones that had no date to begin with, so they are the real test.
The app makes this easier by being explicit about what it did. There is a dry run that shows the changes before any file is touched, and at the end it lists every photo it could not date, rather than quietly leaving them. That list is the useful part: it tells you exactly what is left instead of leaving you to spot-check forty thousand files. The first 500 photos are free, which is plenty to verify against.