JXL to PNG Converter

Encoding: the JXL uses lossy VarDCT or lossless modular coding; existing JPEGs can be repacked without loss; PNG uses lossless DEFLATE with a prediction filter chosen per row, and the download is a lossless 8-bit PNG with full alpha.

Bit depth: 8 to 16 bits per channel, or floating point in the JXL; PNG allows 1, 2, 4, 8 or 16 bits per channel, and the PNG written here has 8 bits per channel. High-bit-depth JPEG XL files are reduced to 8 bits per channel.

Colour: sRGB, Display P3, linear and other spaces described in the codestream in the JXL; PNG supports RGB, greyscale, or an indexed palette of up to 256 colours, written here as 8-bit sRGB.

Transparency: the JXL stores it as an extra channel in the codestream; the PNG keeps it as a full alpha channel, so edges and shadows can fade smoothly.

Animation: frames inside a single codestream; the PNG holds one image, so only the first frame is converted.

Metadata: the JXL can carry EXIF and XMP boxes in the container form, often stripped by encoders; PNG can carry text chunks, an ICC profile, physical resolution and EXIF in an eXIf chunk, but nothing is copied across.

JPEG XL is a next-generation format designed to replace JPEG. It compresses better than JPEG and WebP, supports lossless, HDR and progressive decoding, and can losslessly repack existing JPEGs.

A JPEG XL file is either a bare codestream starting with FF 0A or an ISO base media container whose 'jxlc' box holds the codestream. A recompressed JPEG keeps a 'jbrd' box that lets the original JPEG bytes be rebuilt exactly.

JXL files usually come from image editors, archival pipelines and lossless JPEG recompression.

PNG stores pixels losslessly with full alpha transparency. It is ideal for screenshots, logos, UI and anything with sharp edges, but photos saved as PNG are several times larger than JPEG.

A PNG opens with an 8-byte signature and is a chain of chunks, each with its own CRC: IHDR (size, depth, colour type), optional PLTE and tRNS for palettes, one or more IDAT chunks with the compressed rows, and IEND.

PNG is the better choice for screenshots, logos, graphics and anything that needs transparency, while JXL suits archiving and future-proof high quality storage.

PNG strengths: Lossless: no quality loss, ever; Full transparency with smooth edges; Perfect for text, screenshots and graphics. Drawbacks to weigh: Large files for photographs; No standard animation (that is APNG).