You AirDrop or email a photo from your iPhone, and on a Windows PC, an Android phone, or in an older app, it just won't open. The file extension is .HEIC, and most things outside Apple's ecosystem don't know what to do with it. This isn't a bug - it's a format your iPhone has been quietly switching to since iOS 11.
Why Apple Uses HEIC
HEIC (High Efficiency Image Container) stores photos using the same compression technology as HEVC video (H.265). At the same visual quality, a HEIC file is roughly half the size of an equivalent JPEG. For a phone storing thousands of photos, that's a meaningful amount of space saved - which is why Apple made it the default camera format starting with iOS 11 and the iPhone 7 and later.
The catch: HEIC support outside Apple devices is inconsistent. Windows only added native HEIC viewing in Windows 10/11 with an extra codec pack, most Android phones still don't support it, and a lot of older or simpler software (some web upload forms, some photo editors, some printing services) doesn't support it at all. JPEG, by contrast, has been universally supported since the 1990s.
Does Converting HEIC to JPG Lose Quality?
Barely, if you do it once. Both HEIC and JPEG are lossy formats - they discard some image data to achieve compression - but they discard different things, and HEIC's compression is more efficient. Converting HEIC to JPG at a high quality setting (90%+) produces a JPEG that's visually indistinguishable from the original HEIC in almost all cases, even though it's now a larger file (since JPEG is less efficient at the same quality).
What you should avoid: converting HEIC → JPG → HEIC → JPG repeatedly, or re-saving the same JPEG multiple times after edits. Each lossy re-encode compounds a small amount of quality loss. Convert once, then work from that JPEG.
When to Convert, and to What
- Sending photos to someone on Android or Windows → HEIC to JPG. JPG is the safest universal choice.
- You need transparency, or you're archiving for editing later → HEIC to PNG. PNG is lossless, but files will be considerably larger.
- Uploading to a site that rejects HEIC outright → HEIC to JPG is almost always what these forms expect.
- You just want every photo on your phone to save as JPEG going forward, skip the conversion step entirely: on iPhone, go to Settings → Camera → Formats and choose "Most Compatible" instead of "High Efficiency." This changes future photos only - it won't touch what's already on your camera roll.
Converting in Bulk
If you're clearing out a camera roll full of HEIC files rather than converting one photo at a time, batch conversion is the practical approach - upload the whole folder, pick JPG as the output, and convert everything in one pass rather than repeating the process per file. RunConvert's HEIC converter handles both single files and batches, and deletes uploads automatically once the conversion finishes.
The Short Version
HEIC isn't broken and it isn't a mistake - it's a genuinely more efficient format that just hasn't reached universal support yet. JPEG remains the format everything can open, so when compatibility matters more than file size, convert HEIC to JPG and move on.