HEIC to JPG: why iPhones use HEIC and how to convert without uploading

Photos exported from an iPhone often fail to open on other sites, and people in group chats say they cannot see them. Nothing is broken — it is a format issue.

1. What HEIC is and why Apple uses it

HEIC is HEVC-encoded image data inside the HEIF container. At the same visual quality it is roughly 40% smaller than JPG, which lets an iPhone store more photos and still have room for portrait depth maps and Live Photo data.

The cost is portability. JPG is a 1992 standard that everything reads. HEIC patents are spread across several companies, browser vendors are unwilling to pay for them, and so most browsers still cannot decode HEIC at all.

2. Can a browser convert HEIC locally?

It depends on the browser — and this is where a lot of sites are not honest. Chrome and Firefox cannot decode HEIC;createImageBitmap() and<img> both fail outright. Safari can, because it calls the system decoder on macOS and iOS.

So any site claiming "100% browser-side, nothing uploaded, HEIC supported" is either lying or quietly uploading. What we do instead is tell you the truth: pick a HEIC file here and you get an explicit message that the browser cannot decode it, plus how to export to JPG first.

3. Converting without installing anything

• Settings → Camera → Formats → Most Compatible. New photos are then JPG, about 40% larger each.
• Existing HEIC files: select in Photos → Share → Save to Files. iOS converts to JPG on the way out (iOS 15+).
• AirDrop to a Mac converts to JPG by default. Downloading originals from iCloud Photos keeps HEIC.

4. Compressing afterwards

JPG files converted from HEIC are larger. Compressing right after conversion takes that back. A batch tool can process a whole folder and hand you one ZIP.

Compression here happens in your browser; nothing is uploaded. For personal photos that matters more than any feature list.

5. Quick reference