Why iPhone photos are HEIC, and how to change it

Why your iPhone photos are HEIC

Apple's HEIF and HEVC support page (opens in a new tab) names the two formats: HEIF (High Efficiency Image File Format) for photos and HEVC (High Efficiency Video Coding, also known as H.265) for video. Its stated reason is compression: they "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 calls capturing in these formats recommended.

iOS 11 introduced both. The same page lists the iPhones that can capture them: iPhone 7 and iPhone 7 Plus or later. Apple's WWDC 2017 session on HEIF says iOS 11 can capture and store HEIF images using the HEVC codec, so the extension you meet is .HEIC, and quotes an average of about 2x compression compared with JPEG of the same visual quality, without describing how it was measured. Older iPhones can still view, edit and duplicate such files, with limitations, once they run iOS 11 or later.

So an iPhone 7 or newer writes HEIC unless the setting below says otherwise. For what is inside the file, see what HEIC is.

Switch the camera to JPEG: Settings > Camera > Formats

1. 01

   Open Settings, then tap Camera

   This is the path in Apple's page; the setting sits in the Settings app, not in the Camera app.

2. 02

   Tap Formats

   Apple's guides also put the 12 MP or 24 MP Photo Mode choice and the ProRAW and ProRes switches on this screen, on models that have them.

3. 03

   Tap Most Compatible

   Apple: all new photos and videos then use JPEG or H.264. This row is available only on iPhones and iPads that can capture HEIF or HEVC.

4. 04

   To go back, tap High Efficiency

   Apple: this returns you to the space-saving HEIF and HEVC formats.

For how a Live Photo is stored and what a converter does with it, see Live Photos and HEIC.

What happens when a photo leaves the iPhone

Sharing: Options > Format

Apple's iPhone guide says to open a photo or video, tap the Share button, tap Options, and then pick a format: Automatic for the best format for the destination, Current to prevent a conversion, or Most Compatible, where files may convert to JPEG or MOV. A Live Photo sent to a device or service that does not support Live Photos is shared as a still photo. Apple also notes that sharing includes the photo's metadata, such as date and time, location, device and captions. To send a photo without its location, see removing GPS from HEIC.

USB import: Keep Originals

Apple's page says that when you import HEIF or HEVC media from an attached iPhone or iPad into Photos, Image Capture or a PC, it might be converted to JPEG or H.264, and that to stop this you open Settings, tap Apps, tap Photos, scroll down and tap Keep Originals. Apple's separate transfer guide for Mac and PC (Photos on a Mac, the Apple Devices app on Windows) does not mention conversion or this setting at all, so the HEIF and HEVC page is the only Apple source we found for it.

Older forum answers use different words. A 2018 Apple Community reply and 2020 and 2021 Microsoft Q&A answers describe a section called Transfer to Mac or PC with two options, Automatic and Keep Originals, and quote a description reading "Automatically transfer photos and videos in a compatible format, or always transfer the original file without checking for compatibility." None of those replies carries an Apple staff label, and we could not find the name Transfer to Mac or PC on any Apple page. If your Settings > Photos screen shows that heading, it is the same idea; if your screen differs, trust what it shows.

With iCloud Photos turned on, Apple's transfer guide says to download the original, full-resolution versions to the iPhone before importing to a PC. Apple also says iCloud Photos always uploads and stores your originals, so the cloud copy is the HEIC regardless of what a later import does.

Once a HEIC reaches a computer, opening or converting it is a separate step: see HEIC to JPG on a Mac and opening HEIC on Windows.

I just want it to work: what to do

If you only sometimes need a JPEG, converting at the moment of sharing is the less costly habit. Changing the camera is the right call when most of what you shoot goes straight to places that cannot read HEIC and you accept the larger files.

How much smaller is HEIC, really?

Apple states the direction but publishes no figure on its support page. An Apple engineer's WWDC 2017 talk gives an average of about 2x compression compared with JPEG at the same visual quality, without a method. We measured it ourselves so you can see a method and the spread.

• Method. Python with Pillow 12.3.0 and pillow-heif 1.8.0 (libheif 1.23.4). Each image was encoded to HEIC at quality 50, 60, 70 and 80, decoded, and scored with SSIM (scikit-image, per colour channel) against the original pixels. JPEGs were written with Pillow's libjpeg at every quality from 30 to 99 (4:2:0 subsampling, optimized Huffman tables), and the smallest file whose SSIM was at least the HEIC's was taken.
• Images. Four photographs bundled with scikit-image: an astronaut portrait (NASA, public domain), a coffee cup (CC0, Rachel Michetti), a cat (CC0, Stefan van der Walt) and a rocket launch (SpaceX, public domain). They are small, 0.14 to 0.27 megapixels.
• Limits. The images are small and were JPEG-decoded before our test. The encoder is libheif's HEVC encoder, not Apple's. SSIM is a proxy for visual quality, not a judgement by eye. Read the result as a spread, roughly 45 to 50 percent smaller at HEIC quality 50, narrowing as quality rises. An iPhone photo of a different scene could land elsewhere.

Gotchas

• Screenshots are not always PNG. Apple's screen-capture page says that with Settings > General > Screen Capture set to SDR, screenshots use PNG and recordings use HEVC; set to HDR, screenshots use HEIF and recordings use HEVC (HDR10). The page does not say which is the default, so check the setting on your phone. The Camera format choice does not control this.
• Switching the camera converts nothing. Apple describes the setting as applying to new photos and videos. Your existing library stays as it is.
• The Most Compatible row only exists on iPhones that can capture HEIF or HEVC. Apple says so on its support page.
• JPEG and HEIC are not the only files in your library. ProRAW is a .dng file; ProRes video is its own format. Neither changes when you pick Most Compatible.
• Resolution is a separate choice. On supported models, Settings > Camera > Formats > Photo Mode offers 12 MP or 24 MP, and 48 MP needs Resolution Control or ProRAW & Resolution Control. Apple's guide does not tie these to the HEIC choice, so a JPEG at a higher resolution is still a large file.
• Sharing sends metadata. Apple notes that a shared photo includes date, time, location, device and captions unless you change it. Our JPG, PNG and WebP converters keep the date taken, camera and exposure settings but leave the GPS location out unless you switch on Include location (GPS), so a converted photo does not reveal where it was taken.
• A photo that will not open on Windows is usually a missing codec, not a bad file. See the Windows guide and the troubleshooting page.

Convert the HEIC photos you already have

Our converters write JPG, PNG, WebP, AVIF or PDF. The JPG, PNG and WebP converters copy the photo's date, camera and settings by default and its GPS location only if you ask; AVIF and PDF output carries no Exif. Keep the original HEIC as your full-quality copy: every conversion makes a new lossy file. To check what is inside a HEIC before you decide, open it in HEIC File Checker or the HEIC viewer.

What we could not verify

• Hands-on behaviour. We have no iPhone here. Nothing in this guide comes from tapping through the menus ourselves, and no screenshot of a real iPhone appears in it.
• The default of the USB transfer setting. Apple's current page names Keep Originals under Settings > Apps > Photos. That Automatic is the other option, and that the section was called Transfer to Mac or PC, comes only from forum replies. Apple's page does not say which iOS version introduced the Settings > Apps > Photos path.
• HDR, Live Photos and Portrait depth under Most Compatible. Apple's WWDC 2024 session describes iPhone HDR photos as an SDR image plus a gain map, stored in HEIC and also supported in JPEG, and says iPhones have captured gain maps since 2020. We found no Apple page that says what the camera writes in JPEG mode, or how any converter, ours included, treats the gain map.
• Video file sizes. We did not measure HEVC against H.264. Some third-party pages say 4K at 60 fps and 1080p at 240 fps need High Efficiency; we found no such statement on the Apple pages we read, so we have left it out. Apple does say HEVC support on some older devices depends on resolution and frame rate, with 1080p or lower and 60 fps or lower more broadly compatible.
• When Automatic converts. Apple says shared media might be converted if the receiver does not support the newer formats. We have not tested which receivers trigger it.
• The Convert Image action's options. Apple's Shortcuts guides name the action but we did not find a page listing its formats or quality control.
• The size test is ours, not Apple's. Small public-domain images and a different encoder, as described above.