JXL converter

JXL is technically excellent and practically early: when a .jxl file refuses to open, converting it locally is the quickest fix. These conversions run as WebAssembly inside your browser, so the image itself never travels anywhere.

What is JXL?

JXL (JPEG XL) is the JPEG committee's own successor format, finalized in 2022: a royalty-free codec that beats classic JPEG on compression, supports lossless mode, transparency, HDR and even lossless recompression of existing JPEG files. Adoption has been turbulent: Safari ships it, Chrome removed its experiment, and most desktop software cannot open a .jxl yet, which is precisely when a converter becomes necessary.