JXL to JPG Converter
Reconstruct an original JPEG byte-identically when available, or explicitly create a new lossy JPG from a static JPEG XL image.
Reconstruction is not re-encoding
A JPEG-derived JXL can store the original JPEG structure. Reconstruction restores those exact original bytes. A new JPG encode decodes pixels and compresses them again, so its bytes and pixels may differ.
Format limits stay explicit
PNG and JPG cannot represent every JPEG XL HDR signal, extra channel, animation feature, or metadata box. Animated JXL is never sent to JPG, and animated PNG output uses APNG so frames are not silently discarded.