Your iPhone photos are HEIC. When does that actually matter?
If you have ever emailed a photo from an iPhone to someone on Windows and received a reply saying “I can't open this”, you have met HEIC. It has been the default format for iPhone photos since iOS 11 in 2017, and for most people, most of the time, it causes no trouble at all. The trouble, when it comes, arrives at the edges: sharing, uploading and printing.
What HEIC is
HEIC is a still image compressed with HEVC, a video codec also known as H.265, stored in a container format called HEIF. Because HEVC is far more modern than the maths behind JPG, which dates from the early 1990s, it can describe the same picture in roughly half the space.
That saving matters at phone scale. A typical 12 megapixel iPhone photo is around 1.5 to 2.5 MB as HEIC, against 3 to 5 MB as a JPG of similar quality. Over a few thousand photos a year, that is gigabytes of storage and iCloud space. HEIC can also carry things JPG cannot easily hold, such as depth maps for Portrait mode, and the extra brightness information that makes HDR photos glow on newer screens.
Where it causes problems
Apple's own devices read HEIC natively, and so do recent versions of macOS. Outside that bubble, support is patchy:
- Windows can show HEIC photos, but often only after installing extensions from the Microsoft Store, one of which has at times been a paid download. Plenty of machines never have them.
- Web upload forms such as job applications, government portals, rental applications and school systems frequently accept only JPG, PNG or PDF.
- Print kiosks and online print services vary. Some convert HEIC happily, others reject it.
- Older software, including older versions of editing programs and many photo viewers, cannot open it.
- Web pages: recent Safari can display HEIC; most other browsers cannot, so you cannot put a HEIC straight on a website.
Where it does not
A lot of the time, iOS quietly converts for you. When you share a photo through Mail, Messages to a non-Apple phone, or many third-party apps, the share sheet often sends a JPG. AirDrop between Apple devices keeps HEIC, which is fine because both ends understand it. Social apps upload whatever format they like and convert on their own servers.
So if your photos only ever travel from your phone to social media and to other Apple users, you may never notice HEIC at all.
Three ways to deal with it
1. Switch the camera to JPG
In Settings → Camera → Formats, choose Most Compatible. From then on, the camera saves JPG. You give up the storage saving, and some modes that need High Efficiency, such as 48 MP HEIF Max and certain high frame rate video options. This is the right choice if you are constantly moving photos to Windows or uploading them to forms.
2. Convert automatically when copying to a computer
In Settings → Photos, under Transfer to Mac or PC, choose Automatic. Photos copied over a cable are converted to JPG on the way. The phone keeps its compact HEIC originals. It only helps with cable transfers, not uploads from the phone itself.
3. Convert copies only when you need them
Keep shooting in HEIC and convert just the photos that need to go somewhere fussy. A HEIC to JPG converter does this in seconds, and if it runs in the browser, your photos do not need to leave your device. This keeps the space saving and the extra quality in your library while solving the compatibility problem at the point it arises.
What you lose when converting
Not much that you would notice, but it is worth knowing:
- A little quality. JPG compresses again. At 90 percent quality the difference is invisible in normal viewing.
- HDR brightness. Photos that look extra-bright on a new iPhone screen become ordinary, well-exposed photos. JPG has no widely supported way to carry that range.
- Live Photo motion and depth data. These are separate from the still image and are dropped.
- Metadata, sometimes. Many converters redraw the image and so drop the date, camera details and location. That can be a feature: it stops you sending your home's GPS coordinates to a stranger. If you want to know what is in a photo first, look at it in an EXIF viewer.
The short version
HEIC is a good format with a support problem. If the problem rarely touches you, ignore it. If it bothers you weekly, switch the camera to Most Compatible. If it bothers you now and then, convert on demand and keep the originals as they are.