What is HEIC Format on iPhone

You AirDropped a photo to a friend on Windows and they replied that the file will not open. Or you tried to upload a picture to a job portal and it rejected the extension. Somewhere in that exchange you learned your iPhone has been saving photos as something called HEIC, and you had no idea because iOS shows you a picture, never a format.

Here is what HEIC actually is, why Apple chose it, what you lose by converting away from it, and the one setting that ends the whole problem if you want it ended.

HEIC in one paragraph

HEIC is the file extension for a photo stored in HEIF, which Apple spells out as High Efficiency Image File Format. Apple introduced support for HEIF with iOS 11, and says the iPhone 7 and later can capture it (Apple, HEIF and HEVC media, published 5 Dec 2025). For a side-by-side with JPG, see HEIC vs JPG on iPhone.

The headline claim is smaller files at the same quality. Apple’s wording is that HEIF and HEVC “offer better compression than JPEG and H.264, so they use less storage space on your devices and iCloud Photos, while preserving the same visual quality.” Apple gives no size ratio.

Many pages say about half, but I could not trace that to a primary source, so I do not claim a figure here.

What the HEIF format supports

The size saving gets the attention. On paper the format can do more than that. These points come from the Library of Congress, HEIF with HEVC (HEIC) format description (last updated 2 Nov 2020, read 4 Nov 2026) and the Library of Congress, JPEG page. I have not checked on a device which of them an iPhone photo actually uses.

• More colour depth. HEIF with HEVC compression supports 8, 10, 12 and 16 bit colour. The JPEG family is limited to 8 bits per channel.
• Transparency. HEIF can carry a transparency (alpha) plane, along with depth maps, as auxiliary pictures.
• Multiple images in one file. A HEIF file can hold any number of still images, image sequences and metadata for each. The Library of Congress names Apple’s Live Photo as one multi-picture use of this design.

Those are capabilities of the format, not a promise about every photo your iPhone takes. For everyday use the issue is compatibility.

The compatibility problem

Apple says that when HEIF or HEVC media is shared by AirDrop, Messages or email to a device that cannot read it, it “might automatically be shared in a more compatible format, such as JPEG or H.264” (Apple, HEIF and HEVC media).

On Windows, the Microsoft Store, HEIF Image Extension page says the extension lets Windows read and write HEIF files, and that a video extension package must also be installed to view some of them.

Where a.heic file can be refused:

• Upload forms that accept only a fixed list of extensions, when.heic is not on the list
• Windows PCs without Microsoft’s HEIF extension
• Any app or device that cannot read HEVC compression

The Library of Congress notes that the underlying HEVC encoding is “heavily encumbered with patents”. I am not claiming that is why support varies.

How to tell what format a photo is

I have not checked on a device which Photos screen shows a photo’s format, so I am not giving steps for it. What you can rely on is the extension: a file ending in.heic is a HEIF file with HEVC compression, according to the Library of Congress. If an upload is rejected, check which extension the form accepts before you assume HEIC is the cause.

Turning HEIC off entirely

If you never want to deal with this again, go to Settings, then Camera, then Formats, and choose Most Compatible. Apple’s wording is that all new photos and videos will then use JPEG or H.264 (Apple, HEIF and HEVC media).

What it costs you: storage. Apple says HEIF and HEVC use less space than JPEG and H.264 at the same visual quality, so new photos are expected to take more. Apple gives no ratio, so I will not state one.

There is a second setting worth knowing about. Apple says importing from an iPhone by USB to Photos, Image Capture or a PC may convert the files to JPEG or H.264, and that choosing Keep Originals in the Photos settings stops that (Settings, Apps, Photos, per Apple’s page).

Converting individual photos instead

For one-off photos I use Grabio, a free iOS Shortcut I built. It sits in the share sheet: select a photo, tap Share, tap Grabio, then tap Photo → JPG or Photo → PNG. The same photo menu in the current build also has Compress photo, Resize (1080), Make it square and Remove location (EXIF). I have not tested a large batch.

It is free, there is no account, and there is no App Store install. Get the Shortcut if it sounds useful.

Which target format to convert to

The answer depends on what the photo is.

JPG for photographs going anywhere outside Apple. There is a step by step in converting HEIC to JPG on iPhone. For the specific case of a PC on the other end, see HEIC to JPG for Windows.

PNG for screenshots, graphics, sharp text, or anything needing transparency. PNG is a lossless format. The route is in converting HEIC to PNG on iPhone.

PDF when the form asks for a document rather than a picture, such as scans of forms, receipts or ID copies. Check what the form asks for; the route is in converting HEIC to PDF on iPhone.

One rule to carry with you: convert once, from the original. JPEG’s main modes are lossy (Library of Congress, JPEG), so each extra save as JPG can lose a little more.

Should you convert your whole library?

No. Apple says HEIF takes less space than JPEG, so a JPG copy of your library is expected to take more, and Apple gives no ratio. Converting also adds a lossy generation to every file, for a compatibility problem you probably have with a few photos.

Keep the library in HEIC. Convert the individual photos you need to send, upload or print. Treat the JPG as a disposable export and delete it afterwards.

Frequently asked questions

Is HEIC better than JPG?

On storage, Apple says yes: HEIF has better compression than JPEG at the same visual quality. Apple gives no ratio. JPG wins on one thing that matters enormously, which is how many apps and computers can open it.

Why will Windows not open my HEIC photos?

Windows needs Microsoft’s HEIF Image Extension to read and write HEIF files, and the Store page adds that a video extension package must also be installed to view some of them.

The Library of Congress notes HEVC is heavily encumbered with patents, though I am not claiming that is the reason. If the person you are sending to cannot install it, convert to JPG before sending.

Does converting HEIC to JPG lose quality?

It can, because JPEG’s main modes are lossy (Library of Congress), so keep the original HEIC and convert once from it. How visible the loss is depends on the photo and the settings; I have not measured it.

Will turning on Most Compatible convert the photos I already have?

Apple’s wording covers new photos and videos only: all new ones will use JPEG or H.264. Photos you already have are not mentioned, so convert any you need individually.

What happens to a Live Photo when I convert it?

A JPG holds one still image, so a JPG made from a Live Photo has no motion. If you want it to keep moving, see turning a Live Photo into a GIF.

Do I need an app to convert HEIC on iPhone?

Not necessarily. Apple says HEIF items shared by AirDrop, Messages or email to a device that cannot read them may be shared in a more compatible format automatically. For a photo you want as a JPG yourself, Grabio converts from the share sheet with no App Store install.

Video downloading is the other half of what Grabio handles for free, see the full video downloader for iPhone comparison if that is ever what you need next.