HEIC vs JPG: the differences that matter
Size, quality, compatibility and editing compared, and when converting is worth it.
HEIC and JPG both store photos, and at a glance they look the same. Underneath they are very different formats, built thirty years apart, and each has a clear place.
The short answer
Keep HEIC on your iPhone, where it saves storage and looks identical. Convert to JPG whenever a photo leaves the Apple world: Windows, websites, upload forms, printing and most email. The HEIC to JPG converter does that without uploading anything.
Side by side
| HEIC | JPG | |
|---|---|---|
| Introduced | 2015 standard, iPhone default since 2017 | 1992 |
| File size at similar quality | About half | Baseline |
| Colour depth | Up to 10-bit and more | 8-bit |
| Transparency | Supported | Not supported |
| Several images in one file | Yes (bursts, sequences) | No |
| Opens on Windows by default | No | Yes |
| Accepted by websites and forms | Rarely | Almost always |
Why HEIC files are smaller
JPG compresses an image in fixed 8 by 8 pixel blocks using a method designed in the late 1980s. HEIC uses HEVC, a video codec from 2013, which can use blocks of many sizes, predicts each area from its neighbours and handles gradients and fine detail far better. The practical result is a photo with the same visible quality in roughly half the bytes. On a phone that holds thousands of photos, that saves many gigabytes.
Where HEIC falls down
Compatibility. HEVC is patent-encumbered, so free software, most web browsers and many operating systems do not decode it. Chrome, Edge and Firefox cannot display HEIC images on a web page. Windows needs extra extensions. Most upload forms check the file type and reject anything that is not JPG or PNG. A format that is half the size is no use if the recipient cannot open it.
Quality when you convert
Converting HEIC to JPG decodes the photo and compresses it again, which in theory loses a little detail. In practice, at a JPG quality of 85 to 90 you will not see a difference, even zoomed in. What you will notice is size: expect the JPG to be 1.5 to 2 times larger than the HEIC. If size matters, for example for a website, convert to WebP instead, which lands much closer to HEIC's efficiency and is supported by every current browser.
Editing
For light editing, either format is fine. For serious editing, HEIC's higher colour depth gives a little more room before banding appears in skies and gradients. If you edit in software that does not read HEIC, convert to PNG for a lossless working copy, then export the finished photo as JPG.
A simple rule
- Storing photos on an iPhone or Mac: HEIC.
- Sending, uploading, printing or sharing with Windows users: JPG.
- Putting photos on a website: WebP, or JPG if the platform does not accept WebP.
- Photos for a form with a size limit: compress to the exact KB the form allows, which accepts HEIC directly.