Yes, we know the name of the site
We don’t hate HEIC as a format. We hate it showing up where it isn’t welcome. On your own Apple devices, HEIC is genuinely good: it typically takes about half the space of a JPG at similar quality. If your photo library is full of old JPGs from a previous phone or camera and storage is tight, converting them is a reasonable move.
Good reasons to convert JPG to HEIC
- Save storage. Roughly halving the size of a large JPG collection frees real space on an iPhone, iPad or Mac.
- One format across your library. If everything since 2017 is HEIC, some people like their older photos to match.
- Smaller backups. Fewer gigabytes to copy to an external drive or keep in cloud storage.
Honest caveats before you start
This is the one page on the site where we’ll talk you out of using it if it’s the wrong fit.
| Caveat | What it means for you |
|---|---|
| No quality gain | Re-encoding a JPG never adds detail; it can only keep what’s left |
| No quality slider | One fixed encoder setting for every photo |
| Slower | Several seconds per 12 MP photo, longer on phones |
| No metadata | Date, camera and location are not copied to the HEIC |
| Compatibility | Great on Apple devices; Windows and the web may struggle |
The metadata point matters most. If your library relies on the date taken to stay in order, test a few photos first and see how your Photos app sorts them. Keep your original JPGs until you’re happy.
When to leave JPGs alone
If the photos will be emailed, uploaded to websites, printed or opened on Windows, keep them as JPG. HEIC’s savings aren’t worth the compatibility headaches there, and our HEIC vs JPG comparison explains why. If you simply need smaller JPGs for a form, Compress HEIC is the better tool because it also accepts JPG.
How it works without a server
HEIC encoding is normally a job for native apps. Here an HEVC encoder (kvazaar) is compiled to WebAssembly and runs inside your browser tab, with Web Workers spreading files across your CPU cores. That’s why it’s slower than our HEIC-to-JPG direction, and also why nothing gets uploaded. New to the format? Start with what HEIC is.