Convert HEIC to PNG
Choose PNG when your next editing or image-processing step accepts PNG but cannot read HEIC. PNG saves the rendered pixels without adding JPEG-style lossy compression, which can be useful when you need an intermediate image for further work.
What lossless output does and does not mean
PNG compression is lossless for the pixels being saved. It does not undo any compression in the original HEIC or guarantee preservation of the original color profile, high bit depth, metadata, or HDR appearance through browser decoding. Keep the HEIC original if those properties matter.
Convert with Winzerk
Add HEIC/HEIF files, choose PNG under Convert all to, and leave resizing off if you want the decoded image dimensions. Select Convert All and download the results individually or as a ZIP.
Expect larger photographic files
A detailed phone photograph may produce a much larger PNG than its HEIC source. There is no PNG quality slider in Winzerk: the JPEG/WebP quality control is not used for PNG. Resize only when you need fewer pixels, since reducing dimensions loses detail even though the resulting PNG is losslessly compressed. For ordinary photo sharing with a size limit, JPG may be the more useful output.
Your photos are decoded and converted locally in your browser, not uploaded to Winzerk. Large HEIC collections may work better in smaller batches. Keep your originals and verify the downloads before deleting anything.