Why iPhone Photos Use HEIC

The short answer

Storage. A 12-megapixel iPhone photo saved as JPG is roughly 2–4 megabytes. The same photo saved as HEIC is roughly 1–2 megabytes. Multiply that across the average user's 5,000-photo library and the saving runs into tens of gigabytes — gigabytes that Apple would otherwise be paying to host on iCloud, and that you would otherwise be paying iCloud subscription fees to keep there. Cutting photo storage in half is a meaningful business decision for both sides.

But it's not just storage. HEIC also lets the iPhone capture richer image data — 10-bit color depth, depth maps for portrait mode, motion data for Live Photos, multiple exposures for HDR — that legacy JPG simply cannot represent. Switching the iPhone away from JPG was a precondition for almost every camera feature Apple has shipped in the last seven years.

Why HEIC compresses so well

HEIC is a container format. The actual pixel data inside is compressed using HEVC (also known as H.265), the video codec used for high-end 4K and 8K streaming. HEVC was designed in the 2010s, two decades after the JPEG standard, and it inherits a generation's worth of compression research: intra-prediction (predicting pixel values from neighbours), larger and variable transform blocks (better adaptation to image content), more sophisticated entropy coding, and bit-rate-adaptive deblocking filters.

The result is roughly 2× the compression efficiency of JPEG at matched perceptual quality. That ratio holds across most photographic content; it shrinks for images with very fine detail (where both formats need to spend more bits) and grows for low-texture scenes like sky and water (where HEVC's larger transform blocks dominate).

What the iPhone actually saves

When you press the shutter on an iPhone with 'High Efficiency' enabled (the default), iOS captures the raw sensor data, runs it through Apple's image-processing pipeline (Smart HDR, Deep Fusion, Photonic Engine, Night mode), and saves the resulting RGB image into a HEIC container. If you enabled Live Photos, a 1.5-second 1080p HEVC video clip lives in the same container. If you took a portrait shot, a depth map and a separate 'effect' layer sit alongside the main image. If you used a Photographic Style or applied edits, those are stored as non-destructive metadata that any other Apple device opening the file can re-render.

You can't get any of that into a single JPG. JPG can only hold one 8-bit-per-channel image and a tiny EXIF header. Switching the iPhone's default to JPG means the camera silently throws away the depth map, the motion clip, the higher color precision, and the editing data on every shot.

The catch — compatibility

HEIC works seamlessly inside Apple's ecosystem and degrades gracefully when you AirDrop, share to apps Apple knows can't read it, or upload via iCloud Photo Sharing — those flows transparently transcode to JPG on the fly. The friction is when you bypass the fallback: emailing a HEIC directly from the Files app, attaching to a third-party email client, uploading to a website's file picker, or transferring via USB to a Windows machine. Those flows preserve the original .heic and the destination software has to know how to decode it. Many don't.

Windows 10 and 11 require a free 'HEIF Image Extension' (and a $0.99 'HEVC Video Extension' to fully decode HEIC images that use HEVC compression — which is most of them). Most Android system galleries can't decode HEIC at all without a third-party app. Photoshop's HEIC support arrived in 2021. Many enterprise and government portals — claims systems, photo printers, hospital intake forms — still reject .heic outright.

The result is the familiar 'I can't open this' moment that has launched a million customer-support tickets and made 'HEIC' one of the most-Googled file extensions in the world.

Should you turn HEIC off?

Probably not. Switching to 'Most Compatible' in Settings → Camera → Formats roughly doubles the storage cost of every photo you take from that point on, and silently disables several camera features (Live Photos still work but are stored as a separate .mov file rather than a single bundle, depth data is dropped, and 10-bit color is reduced to 8-bit). The default is reasonable for most people.

The better workflow is to leave HEIC enabled and convert the specific photos you need to share with non-Apple recipients. Converter.Plus does this entirely in your browser — drop the .heic files, choose JPG or PNG, download the result. Your photos never leave your device, the conversion takes seconds, and you keep the storage savings on every photo you don't share.

If you find yourself converting more than a handful of photos every week, that's the case for switching to 'Most Compatible'. For everyone else, leave the default alone.

Will JPG ever come back?

Probably never as the iPhone default. The arrow of progress in image formats points toward more efficient codecs, not less, and Apple has clearly bet on the HEVC/HEIC and increasingly the AVIF/AV1 family for forward-looking image features. The sensible long-term endgame is broader HEIC and AVIF decoder support across the rest of the ecosystem — Windows, Android, web browsers, and legacy software — which is happening, slowly, under the gentle pressure of a billion iPhone users sharing photos every day. Until then, conversion remains the practical answer.