What Is HEIC Format?

HEIC is the photo format your iPhone has used by default since iOS 11, released in 2017. If you've ever transferred photos from your iPhone to a Windows PC or tried to open an iPhone photo in an older app and it failed, you've run into HEIC's compatibility gap. This page explains what HEIC actually is, why Apple uses it, and what to do with HEIC files.

HEIC vs HEIF — What's the Difference?

HEIF (High Efficiency Image File Format) is the container format — the standard developed by the Moving Picture Experts Group (MPEG). HEIC is Apple's specific implementation of HEIF, using HEVC (H.265) video compression for still images.
The .heic file extension is Apple's. Some non-Apple devices save HEIF images with the .heif extension instead. They're technically the same format and behave identically for conversion purposes. When people say "HEIC file," they almost always mean either one.

Why Apple Switched from JPEG to HEIC

Apple introduced HEIC in iOS 11 for two reasons: smaller file sizes and better image quality at those smaller sizes.
A HEIC photo stores the same visual information as a JPEG but uses roughly half the storage. An iPhone photo that would be 5MB as a JPEG typically takes 2–3MB as a HEIC. At a time when the iPhone's camera resolution was increasing every year, HEIC let Apple offer higher-quality photos without filling up storage twice as fast.
The technical reason for this efficiency: HEIC uses HEVC (H.265) compression, the same codec used for 4K video streaming. H.265 is significantly more efficient than the DCT compression JPEG uses — it analyzes larger blocks of an image and uses more sophisticated prediction algorithms to eliminate redundant data.
HEIC also supports features JPEG doesn't, including:

The Problem With HEIC: Compatibility

HEIC is technically superior to JPEG, but it launched before the rest of the software ecosystem was ready for it. The result: a format that's great on Apple devices and problematic everywhere else.
Where HEIC doesn't work (or didn't until recently):
Where HEIC works fine:

How to Tell If a File Is HEIC

HEIC files use the .heic or .heif extension. On iPhone, you won't see extensions — photos are just "photos." The issue surfaces when you transfer them to a computer.
On a Mac, right-click any photo and choose "Get Info" — the file kind will say "HEIF image." On Windows, files transferred from iPhone will show .heic in the filename if extensions are visible, or you can right-click and check "Properties."

How to Open HEIC Files

Your options depend on your operating system:

How to Stop Your iPhone from Shooting in HEIC

If you'd rather not deal with HEIC at all, you can switch your iPhone back to JPEG:
  1. Open Settings
  2. Scroll to Camera
  3. Tap Formats
  4. Select Most Compatible instead of "High Efficiency"
From this point, new photos will save as JPEG. Existing HEIC photos in your library stay as HEIC — this setting only affects new photos going forward.
The downside: JPEG photos take roughly twice the storage. On a 128GB iPhone where you shoot frequently, this can matter.
The better approach for most people: leave the iPhone on HEIC (it's genuinely better), and convert individual files to JPEG when you specifically need compatibility. That's what HEICtoJPG.com is for.

How to Convert HEIC to JPG

The simplest method: go to HEICtoJPG.com, upload your HEIC file, and download the converted JPG. Free, no account required, works in any browser. The JPG will open on any device, in any app, on any website that accepts image uploads.
For batch conversion of many files — if you've accumulated hundreds of iPhone photos that need converting — desktop tools like JPEGmini handle large batches faster than a browser-based converter.