Why iPhone Photos Are HEIC
HEIC is the container Apple ships its iPhone photos in. The codec inside is HEVC, the same family used for 4K video. The reason Apple made the switch back in iOS 11 was size: a HEIC file is usually about half the size of an equivalent JPG with the same visible quality. On a phone shooting forty-megapixel photos all day, that adds up fast.
The trade-off is reach. JPG is supported by every operating system and every piece of software written in the last thirty years. HEIC is supported on iOS, on recent macOS, on Windows 11 if you pay for the HEIF extension, and on a small but growing slice of Android. Most webmail forms, most older photo editors, and most older messaging apps still expect JPG. That gap is the reason this tool exists.