You send a holiday photo to somebody on Windows. It looked fine on your phone, it arrives, and double-clicking it produces a shrug from the computer — or an offer to buy something from the Microsoft Store.
The file is not corrupt and you did nothing wrong. It is in a format the receiving machine was never licensed to read.
The tool Image Converter PNG, JPG, WebP and AVIF in any direction, with transparency handled properly.What HEIC actually is
HEIC stands for High Efficiency Image Container. It is a container — a box — holding one or more images encoded with HEVC, also called H.265, which is a video codec. That last detail is the whole story, and we will come back to it.
Apple switched the iPhone camera to HEIC by default in iOS 11, in September 2017. Every iPhone since has shot it unless the owner changed a setting. The reason was simple and good: HEIC stores the same photograph in roughly half the space of a JPEG at the same visible quality, and it does several things JPEG cannot — 16 bits of colour depth instead of 8, transparency, image sequences, and depth maps for portrait mode.
By every technical measure it is a better format than the one it replaced. JPEG was finalised in 1992.
So why will Windows not open it?
Because HEVC is patented, and the licence costs money.
JPEG's patents expired long ago, which is why every device on earth reads it for free. HEVC is administered by several patent pools, and anyone shipping a decoder owes royalties. Microsoft's response was to split the support in two:
| Extension | What it does | Cost |
|---|---|---|
| HEIF Image Extensions | Reads the container | Free |
| HEVC Video Extensions | Decodes what is inside it | Around a dollar |
You need both, and neither is installed by default. This is why the usual advice — "just install the extension from the Store" — half works: people install the free one, the file still will not open, and they conclude it is broken.
Some PC manufacturers pre-license the HEVC decoder for their own hardware, so the extension appears free on those machines and paid on others. Same operating system, different answer, which does nothing to make this less confusing.
Where else it fails
Windows gets the blame because it is where most people meet the problem, but it is not alone.
- Older Android phones — support arrived in Android 10, so anything older simply cannot.
- Upload forms — job applications, insurance claims, government portals. Their accept lists were written before 2017 and nobody has revisited them.
- Print shops — kiosk software and photo labs are built on JPEG, and a USB stick of HEIC files is a wasted trip.
- Photo editors more than a few years old — many need a plugin, and some never added it.
- Some websites and chat apps — which is why the photo you sent sometimes arrives as an unopenable attachment rather than an image.
Three ways out
1. Convert the photos you have
The fastest fix for photos already taken. JPEG opens everywhere, and at a sensible quality setting the difference is not something you can see on a photograph. The image converter here does it in your browser, so a camera roll never leaves the machine.
It is worth knowing that converting is a second round of lossy compression — HEIC was already lossy — but the alternative is a file nobody can open, which is a worse kind of quality problem. If you are going to edit the picture rather than send it, convert to PNG instead: larger, but nothing further is lost.
2. Stop the iPhone producing them
Settings → Camera → Formats → Most Compatible.
From then on the camera shoots JPEG. You lose the space saving — photos will be roughly twice the size — and you gain never having this conversation again. Note that this changes nothing about photos already on the phone; those are still HEIC and still need converting.
There is a second setting worth knowing, further down: Settings → Photos → Transfer to Mac or PC. Set to Automatic, the phone converts to JPEG as it transfers over a cable. Set to Keep Originals, it hands over the HEIC untouched. Automatic is the friendlier default and a great many people have it on Keep Originals without knowing.
3. Let a share sheet do it
iOS converts on the way out more often than people realise. Mail and most messaging apps send a JPEG copy. AirDrop to a Mac keeps the HEIC. Uploading through Safari to a website usually converts. So "email it to yourself" is a real, if clumsy, converter — and explains why the same photo sometimes arrives openable and sometimes not.
What happens to the date and the location
Worth knowing before you convert a whole camera roll.
A photo carries EXIF metadata: when it was taken, on what, and — if location services were on — exactly where. Whether that survives depends entirely on how the conversion is done. Anything that decodes the picture and draws it fresh, which is how a browser-based converter works, produces a clean image with none of it.
For a photo you are about to publish or send to a stranger, losing it is a feature: GPS coordinates in a holiday photo are a house address, and a surprising number of people have discovered this the hard way. If you need that data kept — for a claim, a court, or your own archive — hold on to the original HEIC files as well. They are the copy that has it.
Should you convert everything?
No. Converting a whole library to JPEG doubles the space it takes and re-compresses every picture for a compatibility problem you only have when you send something to somebody.
The sensible arrangement is the one most people arrive at eventually: keep the originals as HEIC and convert the ones you are sending. If size rather than compatibility is the problem, compressing the JPEG afterwards is the separate second step. The phone stays efficient, the recipient gets something that opens, and nothing is destroyed on the way.
Is HEIC going away?
Not soon, and its replacement has the same problem in a different shape.
AVIF compresses even better and is royalty-free, which removes the licensing objection entirely — browsers all read it now. But support outside browsers is thinner than HEIC's, so saving an AVIF from a website lands you in exactly the same position, just a few years later.
The lesson underneath both is that a format's technical merit has very little to do with whether the machine at the other end can open it. JPEG is thirty years old and mediocre, and it is the one that always works.