What Is HEIC? Understanding Apple's Image Format

If you’ve ever transferred photos from your iPhone to a Windows PC, you’ve probably encountered files with the .heic extension. These files can’t be opened by many programs, leaving you wondering what went wrong. Here’s everything you need to know about HEIC.

HEIC stands for High Efficiency Image Container

HEIC (High Efficiency Image Container) is a file format based on the HEIF (High Efficiency Image Format) standard. Apple adopted HEIC as the default photo format on iPhones starting with iOS 11 in 2017.

The format uses HEVC (H.265) compression to store images at roughly half the file size of JPEG while maintaining the same visual quality. A typical 12-megapixel iPhone photo that would be 3-4 MB as a JPEG comes in at just 1.5-2 MB as HEIC.

Why does Apple use HEIC?

Apple chose HEIC for three practical reasons:

Storage savings. With the average iPhone user taking over 2,000 photos per year, HEIC’s smaller file sizes add up. Users effectively get twice the photo storage without any visible quality loss.

Advanced features. HEIC supports features that JPEG cannot: transparency (like PNG), 16-bit color depth, image sequences (Live Photos), and depth maps from the dual-camera system. One HEIC file can contain all of this data.

Better compression technology. HEVC compression is a generation ahead of the DCT compression used by JPEG, which dates back to 1992. The math is simply more efficient at representing image data.

The compatibility problem

Despite its technical advantages, HEIC has a significant drawback: compatibility. Windows didn’t add native HEIC support until Windows 10 (and even then, it requires a codec download). Many web browsers, image editors, and social media platforms still don’t accept HEIC files directly.

This creates friction every time someone wants to share iPhone photos with non-Apple users, upload images to a website, or use photos in a document.

How to convert HEIC to other formats

The easiest solution is to convert HEIC files to a universally compatible format like JPG or PNG. You can do this directly in your browser at heic.site — files are converted entirely on your device, so nothing gets uploaded to any server.

For bulk conversions, most tools support batch processing. Simply drag multiple HEIC files at once and download them all as a ZIP.

Should you change your iPhone’s photo format?

You can switch your iPhone to capture photos in JPEG instead of HEIC: go to Settings > Camera > Formats and choose “Most Compatible.” However, this doubles your storage usage and disables some camera features.

A better approach is to keep shooting in HEIC (for the storage savings) and convert only when you need to share with non-Apple platforms.

The future of HEIC

HEIC adoption is growing slowly. Google added HEIC support to Chrome in 2023, and more applications add support each year. Eventually, HEIC may become as universally supported as JPEG. But for now, conversion tools remain essential for cross-platform compatibility.