Free online PNG to JXL converter

Source format: PNG

PNG (Portable Network Graphics) is a widely used raster image format known for lossless compression and full support for transparency. It is commonly used by web designers, app developers, photographers, and anyone who needs crisp graphics such as logos, screenshots, icons, and illustrations. PNG is especially popular when image quality must be preserved exactly, because it does not introduce the artifacts associated with lossy formats.

Target format: JXL

JXL (JPEG XL) is a modern image format designed to provide excellent compression efficiency, high image quality, and support for both lossless and lossy encoding. It can handle transparency, animation, and high bit depth, making it suitable for web graphics, archival storage, and image delivery where smaller file sizes are important. Compared with PNG, JXL can often produce significantly smaller files while preserving the same visual quality, especially for images with gradients, screenshots, and detailed graphics.

How to perform the conversion

The easiest way to convert PNG to JXL is to use a converter that supports JPEG XL output. You can convert the file on 101convert.com for free, without installing any software. If you prefer desktop tools, libjxl provides the official JPEG XL encoder and decoder, and some image editors can export to JXL through plugins or built-in support.

1. Open the PNG file in your chosen converter or image tool.
2. Select JXL or JPEG XL as the output format.
3. Choose whether you want lossless output if you need exact preservation of the original image, or lossy output if smaller file size is the priority.
4. Adjust quality or compression settings if the tool offers them.
5. Start the conversion and save the resulting .jxl file.

If you are using command-line tools, the official encoder from libjxl can be used to convert a PNG file to JXL. A typical workflow is to decode or pass the PNG directly through a supported encoder, then write the output as output.jxl. Exact commands vary by platform and package version, so consult the documentation for your installed cjxl tool.

Notes on quality, compatibility, or limitations

PNG to JXL is usually a quality-preserving conversion, but the result depends on whether you choose lossless or lossy encoding. For screenshots, logos, and UI graphics, lossless JXL is often the best choice. For photographs, lossy JXL may reduce file size more effectively.

A key limitation is compatibility: JPEG XL support is still not as universal as PNG support across browsers, operating systems, and older software. If you need maximum compatibility for sharing or publishing, keep the original PNG as a fallback. Also note that converting a PNG to JXL will not improve image detail beyond the source; it can only preserve or compress what is already there.