Why this comparison matters
If you own an iPhone, every photo you take is stored in HEIC format by default — and has been since iOS 11. Hundreds of millions of people are shooting HEIC daily without ever seeing that acronym or understanding why it sometimes causes problems. At the same time, JPEG is the most universally supported image format in history, recognised by literally every device and application on earth. Understanding the trade-offs between these two formats helps you make better decisions about how to store, share, and publish your photos.
What HEIC actually is
HEIC stands for High Efficiency Image Container. It is a file format developed by the Moving Picture Experts Group (MPEG) and adopted by Apple. The actual compression algorithm inside a HEIC file is HEVC (H.265) — the same codec used for 4K video. This lineage is important: H.265 is a highly sophisticated compression algorithm that took years to develop and produces much better quality-to-size ratios than the older compression algorithms inside JPEG.
HEIC is not just about still images either. A single HEIC file can store multiple images (which is how Live Photos work — the main image plus the motion clip), image sequences, depth maps, and wide colour gamut data. It is a container format, not just a compression algorithm.
What JPEG actually is
JPEG (Joint Photographic Experts Group, after the committee that created it) has been the standard for photographic images since 1992. The compression works by dividing the image into 8×8 pixel blocks, applying a mathematical transformation (discrete cosine transform) to each block, and discarding frequency information that the human visual system is least sensitive to. The result is a compressed file where higher quality settings retain more of the original frequency information.
JPEG's age is both its greatest weakness and greatest strength. It is universally supported everywhere — every browser, every operating system, every app, every printer — precisely because it has had over 30 years to be implemented everywhere.
File size comparison
This is where HEIC's advantage is clearest. For equivalent visual quality, HEIC files are roughly half the size of JPEG. A photograph that produces a 6MB JPEG typically produces a 3MB HEIC. Across a phone with 2,000 photos, that is approximately 6GB saved — the difference between needing 128GB or 256GB of storage. Apple implemented HEIC specifically to address storage pressure on iPhones when they made the switch in iOS 11.
Quality comparison
At equivalent file sizes, HEIC produces noticeably better quality than JPEG. HEIC handles smooth colour gradients better (less banding in skies and sunsets), preserves fine detail like hair and grass better, and produces less of the characteristic 8×8 blocking artefacts that JPEG shows at high compression. In practice, at the quality levels both formats use by default, the difference is subtle but measurable with tools and sometimes visible to trained eyes in detailed areas.
Compatibility: HEIC's biggest problem
HEIC has essentially zero compatibility outside the Apple ecosystem. Windows does not support it natively (you can install a codec from the Microsoft Store, but most users never do). Most Android phones cannot display HEIC. Many web browsers historically could not render it. Most image editing software requires a plugin. Practically, this creates friction every time you share a photo outside an Apple device — which is why my HEIC converter exists.
When to use HEIC
HEIC is the right choice when photos stay within the Apple ecosystem: stored on your iPhone, shared via iMessage to other iPhone users, backed up to iCloud, or viewed on a Mac. It gives you better quality at smaller sizes with no compatibility penalty.
When to convert to JPEG
Convert to JPEG before: uploading to websites, emailing to people who may not use Apple devices, sharing in non-Apple messaging apps, submitting to clients or publications, uploading to stock photo sites, or using in any desktop publishing workflow. My HEIC converter does this conversion entirely in your browser — no upload, no quality loss from server-side processing, no file size limits.