Convert JXL to JPEG
Drop JPEG XL (.jxl) files and download JPEGs that open anywhere. JXL is efficient but largely unsupported in browsers and apps today, so JPEG is the format to reach for when an image has to be shared or uploaded now.
JPEG output uses a high-quality setting. Since this re-encodes an already-compressed JXL, it is a second lossy pass, though the difference is usually hard to see at normal sizes.
Transparency becomes white
JPEG cannot store transparency, so transparent areas in the JXL are flattened onto a solid white background. Convert to PNG or WebP to keep the alpha channel.
Decoding note
JXL is not a native browser format, so it is decoded by a built-in engine that loads once per tab the first time you convert one.
Batch and privacy
Add multiple files, convert, and use Download all as ZIP for the whole set. Conversion runs in your browser; nothing is uploaded, and metadata is dropped when the image is re-encoded.