JPEG XL Converter — in your browser
Convert .jxl ⇄ JPG / PNG / WebP without uploading anything. Everything happens locally via WebAssembly, so your images stay on your device.
Client-side · powered by jSquash WASM
100% private: images are processed locally and never uploaded. First JXL conversion downloads a small WebAssembly module (~1–2 MB); after that it's instant. Very large images (40MP+) use significant memory.
Why convert JPEG XL?
JPEG XL compresses better than JPEG and can losslessly shrink existing JPEGs ~20%. But support is uneven — many apps and Chrome (by default) still can't open .jxl, so converting to JPG or PNG makes images universally viewable. Going the other way, encoding to JXL saves storage for archives where you control the viewer.
How it works
- Your file is read into memory in the browser (never sent anywhere).
- It's decoded to raw pixels — JXL via the jSquash WebAssembly decoder, other formats via the browser's native decoder.
- Pixels are re-encoded to your chosen format (JXL via WASM; JPG/PNG/WebP via canvas), and offered as a download.
FAQ
Is there a file-size limit?
No hard limit, but huge images need lots of RAM to decode. If a 48MP image fails on mobile Safari, try a desktop browser.
Does this work offline?
After the WASM module is cached on first use, conversion works without a network connection.
Will quality drop?
PNG is lossless. JPG/WebP/JXL lossy modes use your quality slider; 85 is a good default.
People also ask
What is a good alternative to JPEG XL?
AVIF is the closest alternative for modern, high-compression images and is supported in Chrome, Firefox, Safari, and Edge. WebP is the safest broadly supported choice with both lossy and lossless modes, and PNG remains the standard for lossless work where compatibility matters most. This converter can output any of those from a .jxl file, so you can keep JXL masters and export whichever format your target browsers accept.
Is JPEG XL the same as JPG?
No. JPEG XL (.jxl) is a newer, separate codec standardized as ISO/IEC 18181, while JPG is the classic JPEG format from the early 1990s. JPEG XL offers better compression, lossless mode, HDR, and animation, and it can losslessly recompress an existing JPG into a smaller .jxl file that can be converted back to the identical original bytes.
What is the JPEG XL format?
JPEG XL is a royalty-free raster image format designed as a modern successor to JPEG, PNG, and GIF. It supports lossy and lossless compression, alpha transparency, animation, HDR and wide color gamuts, and progressive decoding, typically at smaller file sizes than older formats. Files use the .jxl extension and the image/jxl MIME type, and the reference encoder and decoder is the open-source libjxl library.
Is JPEG XL free?
Yes. JPEG XL is a royalty-free standard, and its reference implementation, libjxl, is released under a permissive open-source BSD-style license. That means encoders, decoders, and tools such as this converter can use it without licensing fees, unlike some earlier codecs that carried patent royalties.
Why did Chrome remove JPEG XL?
Google removed the experimental JPEG XL flag from Chrome in early 2023 (Chrome 110), saying there was not enough ecosystem interest and that the format did not offer enough benefit over existing codecs to justify maintaining it. The decision was controversial, and many developers and companies publicly asked for it to be reversed. Google has since said it is revisiting JPEG XL support using a new Rust-based decoder, so check a current compatibility table before relying on native display.
Which browsers support JPEG XL?
Safari has supported JPEG XL natively since Safari 17 on macOS, iOS, and iPadOS, and Firefox includes a decoder only in Nightly builds behind a preference. Chrome and Edge dropped their experimental support in 2023, so most Chromium-based browsers still cannot display .jxl images out of the box, although Google has announced work to bring support back. Because this changes over time, verify the current status on a site like caniuse.com, and convert to WebP or PNG for maximum compatibility.