How to convert HEIC to JPG with OnyxPDF
- Drop your .heic or .heif photos into the tool (the 1.3 MB engine loads once, on first use).
- Set the JPG quality if you want something other than the default.
- Click “Convert to JPG”.
- Download the full-resolution JPGs.
Why do it in your browser instead of uploading?
- Full resolution, always — a 4032×3024 iPhone photo converts at 4032×3024.
- No upload: your camera roll never goes to a conversion server.
- Multi-image HEIC files are handled (each image in the container is converted).
- The engine is cached after first use, so later conversions start instantly — and work offline.
Good to know (honest limits)
- The HEIC engine (about 1.3 MB) must load once while you are online; after that it is cached on your device.
- Conversion speed depends on your device — big photos on an old phone take a few seconds each. That is the honest price of not uploading.
- Output is JPG only (the format everything accepts); for PNG, run the JPG through the Image Converter.
Frequently asked questions
Why can’t Windows open my iPhone photos?
iPhones save HEIC, a format Windows and most websites do not accept natively. Converting to JPG makes the photo work everywhere.
Do I lose quality converting HEIC to JPG?
JPG is lossy, but at the default quality the difference is invisible in normal use — and the resolution is never reduced, unlike some free converters’ silent downscale.
Are my photos uploaded for conversion?
No. A libheif engine vendored into this site converts them in your browser. Your photos never leave your device.
Can it convert several photos at once?
Yes — drop a batch and each HEIC is converted in turn.