Convert WebP to JPEG XL
WebP is the most efficient format the web currently uses — but JPEG XL can usually shave a further 10–30% off at the same visual quality, and it brings true-lossless mode and animation to the table. If you maintain an image library or are rebuilding a site's assets, batch-converting WebP to .jxl is a practical way to cut storage and delivery weight once browsers finish adopting JXL. The approach here is honest about sources: most WebP files on the web were lossy-encoded, so this tool defaults to a lossy, quality-guided pass (slider, default 75%) that preserves the look while shrinking the file. If your WebP source was exported losslessly (common for screenshots and graphics), switch Lossless on to keep every pixel. Transparency carries over either way. Everything runs locally: the browser decodes WebP natively and libjxl (via WebAssembly) encodes the .jxl — no uploads, no server, no limits, offline-capable. Fair warning for already-lossy sources: converting a low-quality WebP to JXL only re-wraps that loss; it cannot recover detail. If the source was heavily compressed, the honest move may be keeping WebP or going back to the original image.
Drop WebP files here or click to browse
Processed locally — files never leave your device
How to use
- Drop your WebP files into the box, or click it to browse.
- Leave Lossless off for typical web WebP (quality slider guides the size), or turn it on for lossless sources.
- Encoding runs locally in your browser via WebAssembly.
- Download the converted .jxl images.
Frequently asked questions
How much smaller will .jxl be than WebP?
At the same visual quality, typically 10–30% smaller. The savings depend on content: smooth gradients and screenshots compress well; already-heavily-compressed sources have little left to gain.
Is my WebP uploaded anywhere?
No. WebP decoding uses your browser's native support and JPEG XL encoding runs as WebAssembly in your tab. Nothing is transmitted or stored, and it works offline.
Is my WebP lossy or lossless?
WebP supports both. Most images downloaded from the web are lossy; sources exported from design tools are often lossless. If you don't know, leave Lossless off and use the quality slider — for lossless sources, turning it on guarantees no further loss.
When is converting WebP to JXL a bad idea?
When the WebP was already compressed heavily — re-encoding adds another lossy generation without recovering detail. And anywhere the destination (social platform, email, legacy app) doesn't read .jxl yet, keep WebP.
Can browsers display JPEG XL?
Safari has rendered .jxl still images since version 17 (2023); Firefox 157 (September 2026) enables it by default; Chrome has merged a decoder with default-on support still pending in 2026. As all three engines converge, .jxl becomes the natural next step after WebP — while most apps and platforms still need an encoded output, which is what converting for them is all about.
Does the alpha channel survive?
Yes. Both lossless and quality modes preserve transparency. Transparent WebP logos and overlays convert correctly.
What's the difference from PNG→JXL?
PNG sources are clean and lossless, so PNG to JXL shines in true-lossless mode. WebP sources were usually lossy to begin with, so quality-guided conversion is often the sensible default.
Related tools
Convert from JPEG XL back to JXL to WebP or JXL to JPG. Starting from PNG or JPG instead? See PNG to JXL and JPG to JXL.