What is HEIC, and why does my iPhone use it?
HEIC is the file extension Apple gives to images stored in the HEIF (High Efficiency Image File Format) container, compressed with HEVC (also known as H.265). Apple adopted it as the iPhone camera's default format in iOS 11 back in 2017, because it stores the same photo in far less space than the JPG it replaced — letting you keep more pictures on the same device.
Why are HEIC files so small?
HEIC borrows its compression from HEVC, the same advanced video codec used for 4K streaming. That modern maths squeezes a photo into roughly half the size of an equivalent JPG at similar visual quality. The result is sharper images that take up less storage and upload faster — the whole point of a "high efficiency" format.
What else can a HEIC store?
A HEIC is more than a single picture. The container can also hold a depth map for Portrait mode, the short motion clip behind a Live Photo, image bursts and sequences, and HDR data for richer highlights. It supports an alpha channel for transparency and wide colour too, so a single file can carry a lot more than its JPG predecessor ever could.
Why won't my HEIC open?
The catch is compatibility. HEVC is patent-encumbered, so support is strong across Apple devices but patchy on Windows and Android and limited on the web. That's why an iPhone photo emailed to a colleague so often "just won't open." When you need a file that works everywhere, convert it to a universal format — for the trade-offs, see PNG vs HEIC.
Should you keep using HEIC?
If you live inside Apple's ecosystem, HEIC saves storage with no downside. If you regularly share photos with Windows, Android, or the web, switch the camera to Most Compatible under Settings to save JPG instead, or convert your HEIC files when you send them. To weigh the options, compare PNG vs JPG or start with what is a PNG.
Frequently asked questions
- What does HEIC stand for?
- HEIC stands for High Efficiency Image Container. It's the file extension Apple uses for images stored in the HEIF format and compressed with HEVC (H.265).
- Why won't my HEIC file open on Windows?
- HEIC relies on HEVC, a patent-encumbered codec, so Windows and Android often need an extra plug-in or app to read it. Converting the file to PNG or JPG avoids the problem entirely.
- How do I make my iPhone take JPG photos instead?
- Open Settings, go to Camera, then Formats, and choose Most Compatible. Your iPhone will save new photos as JPG instead of HEIC.
- Does HEIC support transparency?
- Yes. HEIC has an alpha channel and supports wide colour and HDR, so it can store transparency much like PNG while keeping files small.