What Is HEIC? The iPhone Photo Format Explained

If the photos you copied from an iPhone end in .heic and Windows says you need an extension to open them, you are not alone. HEIC is a modern format that Apple has used as its default photo format since 2017; it compresses more efficiently than JPG, but it does not open on every system or in every program. This article explains the difference between HEIC and HEIF, the history of the standard, the internal structure of the file, which devices and browsers support it, the most common problems and how to convert HEIC photos to JPG, PNG or WebP.

What are HEIC and HEIF?

HEIF (High Efficiency Image File Format) is a container format developed by MPEG (the Moving Picture Experts Group) and standardized as ISO/IEC 23008-12. It is designed to store single images, image collections and image sequences together with their metadata.

HEIC is the variant in which the images inside the HEIF container are encoded with HEVC (High Efficiency Video Coding, H.265). The .heic files Apple devices produce are exactly that. The same container works with other codecs too: images encoded with AV1 form the AVIF format. In short, HEIF is the box and HEIC is that box filled with HEVC.

History

• 2015: Technical development inside MPEG took about a year and a half and was finalized in mid-2015.
• 2017: The standard was published as ISO/IEC 23008-12:2017; it was later extended with a corrigendum and amendments and updated in new editions.
• 2017: Apple introduced HEIF and HEVC support with iOS 11 and macOS High Sierra and made them the default capture formats on capable devices. According to Apple's support page, HEIF/HEVC capture is available on iPhone 7 and later.
• Windows 10 version 1803: Windows began reading HEIC through extensions installed from the Microsoft Store.
• Android 9 (2018) and Android 10 (2019): From Android 9, HEIC photos can be opened if the device supports it; Android 10 added support for saving (encoding) as HEIC.
• Safari 17: According to Can I use, Safari on macOS and iOS has displayed HEIF/HEIC images since version 17.0.

Technical structure of a HEIC file

ISOBMFF boxes

HEIF is built on the ISO Base Media File Format (ISOBMFF), the same foundation as MP4 video. The file consists of "boxes", each with a four-character code, a size and a payload. The ftyp box at the start lists the brands the file complies with. Nokia's HEIF technical documentation lists the main brands:

Items, properties and derived images

Still images are stored as "items" inside the meta box. Properties such as dimensions (ispe), color information (colr), rotation (irot) or cropping (clap) are attached to each item. An image can also be derived from other items: the grid type builds a large image from equally sized tiles. Phones often encode large photos as tiles this way, and a HEIC reader stitches the tiles back into the full picture.

Auxiliary images and metadata

An item can be marked as the primary image, a thumbnail or an auxiliary image. Auxiliary images can carry an alpha channel or a depth map, which is how depth information from portrait-mode shots lives in the same file. EXIF and XMP metadata are stored as separate items too.

Color depth and transparency

HEVC supports 10-bit and higher color depths in addition to 8-bit. That is a real advantage over JPG's 8-bit limit for HDR photos and wide color gamuts such as Display P3. Transparency comes from an auxiliary alpha image, although camera photos rarely use it.

Why HEIC? Strengths and weaknesses

Apple's support page states that HEIF and HEVC compress better than JPEG and H.264, using less storage on devices and in iCloud Photos while preserving the same visual quality.

Support

Apple

Since iOS 11 and macOS High Sierra, Apple devices open, edit and share HEIC natively. Under Settings > Camera > Formats, "High Efficiency" captures HEIF/HEVC and "Most Compatible" captures JPEG/H.264.

Windows

According to Microsoft's support page, opening HEIC in the Photos app requires two Microsoft Store extensions: HEIF Image Extensions (free) and HEVC Video Extensions (US$0.99). Microsoft notes that you need both even if you only work with photos.

Android and browsers

According to Android's developer documentation, opening (decoding) HEIC is available from Android 9 depending on the device, and saving (encoding) as HEIC arrived with Android 10; in practice, support still varies by manufacturer and app. On the browser side, Can I use shows that as of October 2026 only Safari (17.0 and later) supports HEIF images, while Chrome, Edge, Firefox and Samsung Internet do not, which amounts to about 16.93% of global usage. Putting a HEIC image on a website therefore means most visitors cannot see it.

Common problems and how to fix them

HEIC files will not open on Windows

There are three ways out: install the HEIF and HEVC extensions from the Microsoft Store, change the transfer setting on the iPhone, or convert the file to a universal format. For a one-off need the fastest route is converting HEIC to JPG: JPG opens in every program, on every site and on every operating system.

A website or form rejects HEIC

Official application forms, e-commerce dashboards and print services often accept only JPG and PNG. Converting the photo to JPG fixes this. If you plan to edit and want no extra loss, HEIC to PNG gives a lossless copy, although the PNG will be much larger than the HEIC.

I want to publish the photos on a website

Since most browsers do not display HEIC, converting HEIC to WebP is a good choice: WebP works in every current browser and is usually smaller than a JPG of the same quality.

Photos arrive sometimes as JPG, sometimes as HEIC

According to Apple's support page, if you do not want photos converted to JPEG when importing over USB, open Settings > Apps > Photos and choose Keep Originals. With that option off, the iPhone may convert photos to a more compatible format during transfer. To capture new photos as JPG directly, set the Camera format to "Most Compatible"; the files will take more space.

Colors look slightly different after conversion

iPhone photos are often saved in a wide color space such as Display P3, with HDR information. When converted to a standard JPG, colors are adapted to sRGB, which screens and the web expect; small shifts in saturated reds and greens are normal.

Conversion tips

• JPG for general use: For e-mail, forms and sharing, the default 90% quality is a good balance. Because HEIC compresses more efficiently, the JPG is usually larger than the HEIC.
• PNG for editing and archiving: Lossless, but several times larger; convert only the photos that really need it.
• WebP for the web: Broad browser support and small files.
• Batches: You can add several photos at once and convert them in one go.
• If there is a size limit: Shrink the converted JPG to a target file size with compress image, which runs in your browser.

Note: because most browsers cannot decode HEIC, on our HEIC conversion pages the photos are uploaded to our servers over a secure connection, converted there and deleted within 30 minutes at the latest.

Frequently Asked Questions

Are HEIC and HEIF the same?

Not exactly. HEIF is the name of the container format; HEIC files are HEIF files whose images are encoded with HEVC. Apple devices produce HEIC, and in everyday use the two terms are often used interchangeably.

Does converting HEIC to JPG reduce quality?

JPG is lossy, so a little detail is lost, but at 90% quality the difference is hard to see. 10-bit color and HDR information are reduced to 8 bits in the JPG.

How do I make my iPhone shoot JPG?

Choose "Most Compatible" under Settings > Camera > Formats. New photos will then be saved as JPEG and videos as H.264; existing HEIC photos stay as they are.

Why are HEIC files smaller than JPG?

HEVC is a much newer and more advanced compression method than JPEG. It splits the picture into more flexible blocks and uses better prediction, so it reaches similar visual quality with less data.

Why won't a HEIC image open in Chrome?

According to Can I use, Chrome, Edge and Firefox do not support HEIF/HEIC images; only Safari 17 and later does. Convert the photo to JPG or WebP to share it on the web.

Sources

• Apple Support: Using HEIF or HEVC media on Apple devices
• Microsoft Support: Photos app error "Can't view this file type"
• Nokia Technologies: HEIF technical information
• Nokia Technologies: High Efficiency Image File Format (HEIF)
• EVS (Estonian Centre for Standardisation): ISO/IEC 23008-12:2017 record and later editions
• Can I use: HEIF/HEIC image format
• Supported media formats (Android Developers)
• Wikipedia: High Efficiency Image File Format