You AirDrop or email a photo from your iPhone, open it on a Windows PC or upload it to a website, and… it won't open. The culprit is almost always HEIC, the format modern iPhones use to save photos.
Why iPhones use HEIC
HEIC (based on the HEIF standard) stores the same quality as JPG in roughly half the file size, which saves space on your phone. Apple made it the default a few years ago. The downside is compatibility: plenty of Windows apps, older devices and web forms simply don't recognise it.
The quickest fix: convert to JPG
JPG opens literally everywhere, so converting is the reliable solution.
- Open HEIC to JPG.
- Drop in your .heic file (or several).
- Download standard JPGs.
The conversion happens in your browser — your photos are never uploaded, which matters when the images are personal.
Stop your iPhone making HEIC in the first place
If you'd rather avoid the whole issue, you can tell your iPhone to shoot in JPG:
Settings → Camera → Formats → Most Compatible.
From then on new photos are saved as JPG. Note that this slightly increases how much space each photo uses.
Bonus: turn those photos into a PDF
Once you've got JPGs, you can bundle several into a single document with Image to PDF — handy for sending a batch of receipts, notes or scanned pages as one file.