The blank square is a rite of passage for new iPhone owners on Windows: the photo exists, the file is there, and the system refuses to show it. The cause is a bet Apple made in 2017, and the fix depends on which of three situations you are in.
What HEIC actually is
HEIC is a container for still images compressed with HEVC — the same codec family as 4K video. Apple adopted it with iOS 11 because it stores a photo at roughly half the size of an equivalent JPG with no visible quality loss, which matters when your camera shoots 48-megapixel frames. The trade-off is the codec: HEVC is patent-encumbered, and most software vendors outside Apple's ecosystem declined to ship a decoder. Windows still treats the format as an optional paid extension rather than a built-in; browsers only recently gained decode support; plenty of web forms and print shops still accept only JPG, PNG or PDF.
Where it actually bites
Four places, in order of frequency: a fresh Windows machine showing thumbnails but no images; upload forms rejecting the file with a generic error; print shops asking you to resend as JPG; and older Android or Linux viewers refusing to open a folder of vacation photos someone AirDropped over. None of these are data problems — the file is a perfectly good image, just written in a codec the other side never bought.
The three routes, and when each one is right
- Change the camera setting. iPhone Settings → Camera → Formats → Most Compatible shoots JPG from then on. Free and permanent — at the cost of roughly doubling your photo storage for every shot from now on. It does not help with the photos you already have.
- Convert on the fly while sharing. Sharing a photo through most chat apps or AirDrop to a Mac converts it automatically. Convenient when it works, but you cannot pick the quality, and it does nothing for a file you need on Windows.
- Convert the files you have. The right answer when the photos already exist and need to go somewhere specific — an upload form, a print order, a client. This is exactly what a converter is for, and it is a one-time decision about which one to trust.
What to check in a converter
Quality control, first: some tools always re-encode at their own default, which can quietly re-compress a photo a second time if you then edit the JPG. Batch support, second — converting a camera roll one file at a time is an evening of clicking. Then the details people discover too late: whether the capture date and GPS tags survive (EXIF), whether a rotated photo comes out sideways, whether free means watermarks or a three-file limit, and where the files are processed. Uploading personal photos to an unknown server is the one part of this pipeline with a real privacy cost, and server-side converters are also slower than your own machine.
The HEIC converter on this site runs the decode in the browser tab itself — no upload, no account, no watermark, batch of any size — and keeps the EXIF block on JPG output so dates and locations survive. Drop a batch in, pick JPG (or PNG, or WebP if you are heading for the web), and the files come back upright and ready for wherever they need to go. It works in Safari on the iPhone itself, which is the least roundabout option of all: convert where the photos already live.