HEIC to JPG Converter

Why iPhones use HEIC

HEIC (High Efficiency Image Container) stores a photo compressed with HEVC, the same codec used for modern video. It keeps the same visual quality as JPG in roughly half the space, which is why iPhones have saved photos as HEIC by default since iOS 11. The catch is compatibility: many Windows apps, websites, upload forms and older software still can't open it, which is when converting to JPG helps.

How the conversion works

The tool first asks your browser to read the photo itself. Safari on Mac, iPhone and iPad can usually do that, so nothing extra is downloaded. Other browsers can't read HEIC, so the first time you add one the page downloads a HEIC decoder (about 0.5 MB compressed) and decodes in a background worker so the page stays responsive. The decoder is libheif with the libde265 HEVC decoder, open-source libraries licensed under the GNU LGPL 3.0, compiled to WebAssembly by the libheif-js project; their source code is published at github.com/strukturag/libheif, github.com/strukturag/libde265 and github.com/catdad-experiments/libheif-js.

If a file holds several images, such as a burst, the primary photo is converted. Rotation stored in the file is applied. iPhone photos are usually in the wide Display P3 colour space; the decoder output is tagged as P3 and converted to standard sRGB when the JPG is made, so colours don't look washed out.

Sizes and limits

You can add up to 50 files at a time, each up to 50 MB and 50 megapixels. Larger images are refused with a message instead of being loaded, so the tab doesn't run out of memory. Output keeps the full resolution unless the browser can't allocate a canvas that big (some mobile browsers stop at about 16.7 megapixels); then it's scaled down to fit and the file is labelled.

Privacy and metadata

Files are read, decoded and encoded by your own browser with the Canvas API. Nothing is uploaded, and the download is created on your device, so it's safe for personal photos and work documents.

Converted files contain only the image. EXIF metadata such as the camera model, the date taken and GPS location is not copied. Photos that rely on an orientation tag are rotated upright first, so they still display the right way round. That also means the JPG won't carry the original date taken.