What this does
Converts HEIC/HEIF photos from Apple devices into PNG files, right in your browser. PNG is lossless, so whatever the WASM decoder recovers from the HEIC is preserved exactly — nothing is re-compressed away.
When should I pick PNG over JPG?
- You'll edit the photo afterwards. Every JPG re-save compounds compression artifacts; PNG round-trips through editors cleanly.
- Screenshots and graphics saved as HEIC. Sharp edges and text smear in JPG but stay crisp in PNG.
- You need transparency. JPG flattens alpha channels; PNG keeps them.
The trade-off is size: a PNG of a photograph is typically 5–10× larger than a JPG of the same image. For sharing snapshots, the HEIC to JPG converter is usually the better fit.
How does the conversion work?
HEIC isn't supported by browser <img> decoding, so this
page lazy-loads a WebAssembly HEVC decoder, unpacks each photo locally,
paints it to a canvas, and encodes the canvas as PNG. Up to 20 files per
batch, 50 MB each. There is no quality slider because PNG has no quality
setting — it's lossless by definition.
Why are my PNG files so much bigger than the HEIC originals?
HEIC uses modern video-codec compression (HEVC) tuned for photos; PNG uses general-purpose lossless compression from the 1990s. A 2 MB HEIC can easily become a 15 MB PNG. That's expected — you're trading file size for a format that opens everywhere and never degrades.
Do my photos get uploaded?
No. The decoder runs in your tab via WebAssembly, and the PNG is assembled by your browser's canvas API. Check DevTools → Network if you'd like to see for yourself: no photo data leaves your device.