HEIC to JPG: Why Your iPhone Photos Will Not Open, and How to Convert Them

You emailed a photo to somebody and they replied that it will not open. The file is called something like IMG_4417.HEIC, your phone displays it perfectly, and their computer treats it as an unknown object. Nothing is broken. You have simply run into the gap between what Apple decided to store and what the rest of the world can read.

This guide explains what the format actually is, which of the four conversion routes suits which situation, and the two iPhone settings that stop the problem recurring.

What HEIC is, and why Apple switched#

HEIC is a container. Inside it sits an image encoded with HEIF, the High Efficiency Image File Format, which uses the same compression techniques as modern video codecs rather than the decades-old maths behind JPEG. The practical result is that a HEIC photograph holds roughly the visual quality of a JPEG in about half the bytes.

That is a genuine advance, and Apple's reasoning was sound. A phone with a 48-megapixel camera and a fixed amount of storage benefits enormously from halving the size of every photograph. iOS has shot HEIC by default since iOS 11 in 2017.

The container also does things JPEG cannot. It can hold multiple images in one file, which is how Live Photos and burst sequences are stored. It supports transparency, and depth maps, and image sequences. It handles more than eight bits per colour channel, which matters for HDR.

None of that helps when the person you sent it to is running software from 2019.

Where HEIC actually fails#

The compatibility picture is uneven in a way that is hard to predict, which is what makes this frustrating:

• Apple devices read it natively and always have.
• Windows 11 handles HEIF in more configurations than Windows 10 did, but on plenty of machines the codec is still a separate install from the Microsoft Store, and it has at times been a paid extension.
• Android support arrived in Android 10 and is generally fine on recent phones.
• Web browsers largely do not display HEIC. This is the one that surprises people: you cannot simply drop a .heic into an <img> tag and expect it to render.
• Application software is the real minefield. Anything that predates 2017, and a good deal that does not, has no decoder. Photo printing services, older versions of Photoshop, upload forms on job sites and government portals, editing tools built into content management systems — all of these reject HEIC routinely.

The pattern is that HEIC works beautifully inside Apple's ecosystem and becomes a liability the moment a file crosses out of it. Sending one to somebody is a bet on a setup you cannot see.

The four ways to convert, and when each is right#

Change the setting so it never happens again#

The permanent fix is on the phone, not the file. On iOS: Settings → Camera → Formats → Most Compatible. From that point the camera shoots JPEG.

The cost is real — your photographs will occupy roughly twice the storage — and for most people that is a fair trade against never having this conversation again. If you shoot a great deal and storage is tight, leave it on High Efficiency and convert on the way out instead.

There is a second setting people miss. Under Settings → Photos → Transfer to Mac or PC, the option Automatic converts HEIC to JPEG as it transfers to a computer, while Keep Originals sends the file untouched. If your photos arrive on a PC as HEIC and you would rather they did not, this is the switch.

Let the share sheet do it#

For one or two photos, iOS often converts silently. Sharing a photo into Mail, into most messaging apps, or into any app that has asked for a compatible format, produces a JPEG at the other end. This is why the problem seems intermittent: some of your photos arrive fine and some do not, depending on which route they took out of the phone.

What does not convert is AirDrop with Keep Originals set, and anything that copies the file directly off the device.

Convert on the desktop#

On a Mac, Preview will open a HEIC and export it as JPEG, and for a batch, Automator or the Quick Actions menu will do a folder at a time without any additional software.

On Windows, install the HEIF codec from the Microsoft Store and Photos will open the files; from there it is a save-as. Both routes work and neither is quick for a hundred photographs.

Convert in the browser#

A browser-based converter is the right answer when you have a handful of files, no software installed, and no wish to hand a personal photograph to a stranger.

The distinction that matters is where the file goes. Most online converters upload your image to a server, convert it there, and give you a download link. Your photograph is now on somebody else's machine, covered by a retention policy you have not read, at a company you found through a search result. For a screenshot of a spreadsheet that may be fine. For photographs of your children, it is not.

A converter that runs entirely in your browser never transmits the file. The conversion happens in the page, on your own processor, and the result is written straight back to your downloads folder. The image compressor on this site works that way for JPEG, PNG and WebP — the files are read into browser memory and never leave the device.

A note on honesty here: browser decoding of HEIC specifically depends on what your browser supports, and Safari on Apple hardware is currently the reliable case because the decoder is in the operating system. On Windows Chrome, a browser tool generally cannot read HEIC without shipping a large decoding library. If a browser-based tool converts your HEIC instantly on a Mac and refuses on a PC, that is why.

JPG or PNG?#

For a photograph, JPG. This is not a close call, and the number of people converting HEIC to PNG suggests it is not obvious.

PNG is lossless: it reproduces every pixel exactly. That is the right property for a screenshot, a logo, a diagram, or anything with hard edges and flat colour, and it is the wrong property for a photograph. Photographs are full of gentle gradients and sensor noise, which lossless compression cannot do anything useful with. Convert a 2 MB HEIC photograph to PNG and you can easily end up with a 12 MB file that looks identical to a 1.5 MB JPEG.

The rule of thumb:

If the destination is a web page rather than a person, skip JPEG and go to WebP. It is meaningfully smaller at the same quality, and browser support has not been a real constraint for several years. Our guide on JPG, PNG and WebP works through the trade-offs in detail.

What conversion costs you#

Both HEIC and JPEG are lossy. Converting means decoding the HEIC back to pixels and re-encoding those pixels as JPEG, and that second encode discards detail of its own. This is called generation loss.

In practice, one conversion at a sensible quality setting is not visible. The damage comes from repetition: convert, edit, save, send, someone else converts again, and after four or five rounds the sky starts to band and edges pick up a halo.

Two habits avoid it entirely:

1. Keep the original. Convert a copy. The HEIC on your phone is the highest-quality version you will ever have of that photograph.
2. Convert once, at the end. Do any editing on the original, and convert only when you are ready to send. Every intermediate save in a lossy format is a small permanent cost.

Sending photos to someone who cannot open them#

If you are reading this because somebody could not open a file you sent, the fastest resolution is usually not a converter at all:

• Email from the Photos app rather than attaching the file from Files. iOS converts on the way out.
• Ask which they need. A print shop that rejected your upload will usually specify JPEG at a minimum resolution, and knowing that saves you converting to the wrong thing.
• Reduce the size while you are at it. A 6 MB photograph attached to an email is a nuisance for the recipient even if it opens. Our guide on compressing photographs for email covers where the real limits are.

The short version#

HEIC is a better format than JPEG by every technical measure and worse by the only one that matters when you are sending a file to somebody else. Inside Apple's world it is invisible and excellent. Outside it, it is a file your recipient cannot open.

Decide which side of that you live on. If most of your photographs stay on your phone, leave High Efficiency on and convert the occasional file you send. If you constantly move photographs to other people and other machines, switch the camera to Most Compatible and accept the storage cost — the setting takes ten seconds and removes the problem permanently.