Starting with iOS 11, iPhones store photos in HEIC format by default. HEIC — High Efficiency Image Container — is technically impressive: it produces images with approximately half the file size of similar JPEGs maintaining high photo quality.
Yet there is a major problem. HEIC is an Apple-centric format not broadly compatible beyond the Apple ecosystem. PC users, non-Apple phones and many websites cannot open HEIC photos lacking extra apps.
Converting HEIC to JPG is the critical process that makes iPhone images compatible everywhere. Common scenarios where this becomes a problem involve sharing photos to Windows users, posting pictures to websites incompatible with HEIC.
People with Macs have the easiest process. Open the HEIC photo in Preview, select File, get more info then Export and pick JPEG as the output format.
Windows PC users, web-based converters handle HEIC to JPG conversion requiring no downloads. Select the HEIC image and get the converted JPG.
Use alljpgconverters.com offering a completely free online HEIC to JPG solution with no download required.