What is HEIC? Everything You Need to Know
What Does HEIC Stand For?
HEIC stands for High Efficiency Image Container. It is a file format for storing individual images and image sequences, developed by the Moving Picture Experts Group (MPEG) as part of the HEIF (High Efficiency Image Format) standard. Apple adopted HEIC as the default photo format starting with iOS 11 in 2017.
The “High Efficiency” in the name refers to the compression technology: HEIC uses HEVC (H.265) encoding, the same codec used for 4K video streaming. This allows HEIC to store images at roughly half the file size of JPEG while maintaining equivalent visual quality.
How HEIC Works
Traditional JPEG compression divides an image into 8×8 pixel blocks and processes each block independently. HEIC takes a more sophisticated approach:
- Larger block sizes: HEIC can use blocks up to 64×64 pixels, allowing it to represent smooth gradients more efficiently
- Predictive coding: Instead of storing every pixel, HEIC predicts pixel values from neighboring blocks and only stores the difference
- Better motion compensation: For image sequences (like Live Photos), HEIC references previous frames to reduce redundancy
- Advanced filtering: Deblocking and sample adaptive offset filters reduce visible artifacts
The result is a format that achieves significantly better compression ratios than JPEG while producing fewer visible artifacts at equivalent file sizes.
Advantages of HEIC
Smaller File Sizes
The most significant advantage is file size reduction. A typical 12-megapixel iPhone photo saved as HEIC is approximately 1.5-2MB, while the same photo as JPEG would be 3-5MB at similar quality. Over thousands of photos, this saves gigabytes of storage space.
Better Quality at Same Size
If you compare a HEIC and JPEG file at the same file size, the HEIC image will look noticeably better. It preserves more detail, shows fewer compression artifacts, and handles gradients more smoothly.
Extended Features
HEIC supports several features that JPEG cannot:
- Depth information: Stores depth maps for portrait mode effects
- Live Photos: Combines a still image with a short video clip in a single file
- Burst sequences: Stores multiple photos in a single container
- Thumbnail embedding: Includes multiple resolution thumbnails for faster browsing
- Wide color gamut: Supports Display P3 color space for richer colors on compatible displays
- 10-bit color depth: Compared to JPEG’s 8-bit, this provides smoother gradients
Disadvantages of HEIC
Compatibility Issues
This is the biggest drawback. HEIC is not universally supported:
- Windows: Native support was added in Windows 10 (1809), but requires the HEIF Image Extension from the Microsoft Store. Earlier Windows versions cannot open HEIC files at all.
- Android: Android 9+ supports HEIC, but many Android devices still default to JPEG and some apps cannot handle HEIC.
- Web browsers: Most modern browsers can display HEIC, but some older versions cannot.
- Social media: Most platforms convert HEIC to JPEG during upload, but some reject HEIC outright.
- Professional software: Some older versions of Photoshop, Lightroom, and other editing tools may not support HEIC natively.
No Progressive Rendering
Unlike JPEG, which can display a low-resolution preview while the rest of the file loads, HEIC does not support progressive rendering. This means images take longer to appear on slow connections.
Editing Limitations
Because HEIC uses more complex compression, editing and re-saving HEIC files can be slower. Some editing applications convert HEIC to a working format internally, then re-encode on save, adding processing time.
HEIC vs JPEG: Quick Comparison
| Feature | HEIC | JPEG |
|---|---|---|
| Compression | HEVC/H.265 | DCT-based |
| Typical file size | 1.5-2 MB | 3-5 MB |
| Quality at same size | Better | Lower |
| Transparency | No | No |
| Depth data | Yes | No |
| Live Photos | Yes | No |
| Color depth | 10-bit | 8-bit |
| Universal support | No | Yes |
| Progressive loading | No | Yes |
How to Handle HEIC Files
On iPhone
Your iPhone already handles HEIC natively. If you need to share a photo with someone who might not have HEIC support, iOS can automatically convert to JPEG when sharing. Go to Settings → Photos → Transfer to Mac or PC → select Automatic.
On Windows
Install the HEIF Image Extension and HEVC Video Extensions from the Microsoft Store. This enables native HEIC viewing in the Photos app and File Explorer.
Alternatively, use a free online tool like PicKit’s HEIC to JPG converter to convert files instantly in your browser without installing anything.
On Mac
macOS High Sierra and later support HEIC natively in Preview, Photos, and Quick Look. You can also convert by opening in Preview and using File → Export to save as JPEG or PNG.
On the Web
If you need to use HEIC images on a website or upload them to a platform that does not support HEIC, convert them first:
- For photos: Convert HEIC to JPG for the smallest file size
- For images needing transparency: Convert HEIC to PNG for lossless quality with alpha channel support
- For batch conversion: Use the batch process tool to convert multiple files at once
Should You Keep Using HEIC?
For most iPhone users, the answer is yes. The storage savings are substantial, and compatibility continues to improve. The practical approach is:
- Keep HEIC as your default on iPhone to save storage
- Convert when needed for sharing, uploading, or working with incompatible software
- Use online tools for quick conversions rather than changing your phone settings
This gives you the best of both worlds: efficient storage on your device and easy conversion when compatibility is required.