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Why Does iPhone Use HEIC Instead of JPG?

Every iPhone since the iPhone 7 (running iOS 11 or later) captures photos in HEIC format by default instead of the universally compatible JPG. This wasn’t an arbitrary choice — there were clear technical and strategic reasons behind Apple’s decision.

The storage problem

Modern iPhones capture increasingly large photos. The iPhone 15 Pro shoots 48-megapixel images, and each generation adds new camera capabilities that produce larger files. Meanwhile, base storage configurations start at 128 GB, shared between apps, videos, system data, and photos.

HEIC compresses photos to roughly half the size of equivalent JPGs. For a user with 5,000 photos on their device, that’s the difference between 15 GB and 30 GB of storage. With iCloud storage tiers at $0.99/month for 50 GB, Apple had a financial incentive to reduce photo sizes — fewer users hitting storage limits means fewer frustrated customers and less iCloud infrastructure cost.

Superior compression technology

HEIC uses HEVC (H.265) compression, the same codec used for 4K video. HEVC was designed by the Joint Collaborative Team on Video Coding and ratified in 2013. It represents a generational leap over the DCT compression in JPEG, which was standardized in 1992.

The key improvements include:

  • Variable block sizes (from 4x4 to 64x64 pixels) versus JPEG’s fixed 8x8 blocks
  • Better prediction modes that reference surrounding pixels more efficiently
  • In-loop deblocking filters that reduce blocking artifacts at low bitrates

The result: same visual quality at roughly half the file size, or noticeably better quality at the same file size.

Features that JPG can’t support

HEIC isn’t just a better compressor — it’s a more capable container:

Live Photos store a still image and a short video clip together in one HEIC file. This would require two separate files in JPG format.

Depth maps from the dual and triple camera systems are embedded alongside the main image, enabling Portrait Mode’s background blur to be adjusted after the fact.

16-bit color preserves more tonal information than JPG’s 8-bit limit, giving Apple’s computational photography pipeline more data to work with during processing.

Image sequences allow Apple to store burst mode shots efficiently in a single container.

Apple’s ecosystem advantage

There’s also a strategic dimension. HEIC creates a minor friction point when moving photos outside the Apple ecosystem. While Apple’s built-in share sheet automatically converts HEIC to JPG when sending to non-Apple devices, the format still causes confusion when users access files directly (through AirDrop to a Mac, syncing via cable, or accessing iCloud photos from Windows).

This isn’t necessarily intentional lock-in — Apple provides the conversion tools built into macOS and iOS. But it does create a smoother experience for users who stay within the Apple ecosystem versus those who mix platforms.

Why not switch to a more open format?

Apple could have chosen WebP or AVIF, both of which offer similar compression improvements over JPEG. However:

  • WebP (by Google) didn’t support all the features Apple needed in 2017, particularly Live Photos and depth maps
  • AVIF (based on AV1) wasn’t standardized until 2019, two years after Apple needed a solution
  • HEIF/HEVC was already standardized, well-tested, and had hardware decoder support in Apple’s A-series chips

Hardware support is critical: encoding and decoding in the dedicated media engine uses minimal battery, while software-based codecs would drain power quickly during burst photography.

How to handle HEIC on non-Apple devices

If you regularly receive HEIC files from iPhone users, the simplest approach is to convert them as needed. Visit heic.site to convert HEIC files to JPG, PNG, WebP, or AVIF directly in your browser — no software installation required, and your files never leave your device.

You can also ask iPhone users to change their camera settings (Settings > Camera > Formats > Most Compatible), but this doubles their storage usage and disables features like Live Photos depth data.