WebP to JXL Converter
Convert WebP to JXL in your browser. WebP files usually come from websites, Chrome's Save image as, CDNs and Android apps; JXL is the better fit for archiving and future-proof high quality storage. You get a JPEG XL encoded with libjxl compiled to WebAssembly, lossy at the quality you choose or lossless. Nothing is uploaded.
- Processed locally
- No upload, no wait
- No sign-up
- No watermark
Drop images here
or choose files · paste with Ctrl/⌘ V
WebP expected · other image formats also work
How to use WebP to JXL
- 1
Add your WebP files: drop them here, choose them, or paste from the clipboard.
- 2
Set the quality.
- 3
Click Convert. Each file is decoded and encoded in a background thread on this device.
- 4
Download the .jxl files one at a time or together as a ZIP.
Why use Aback Images for webp to jxl
Where the JXL goes next
JXL opens in Safari 17+, macOS 14 and iOS 17, GIMP, Krita, ImageMagick and the libjxl tools.
JXL next to WebP
Both formats are lossy, so the size mostly follows the quality setting; at the default the JXL usually lands in the same range as the WebP.
A second lossy pass
WebP is lossy already, since it stores lossy VP8 coding or lossless VP8L, so keep the quality at or above the default to avoid stacking a new layer of artefacts on the old one.
Processed on your device
Your images are decoded, edited and encoded inside this browser tab by Web Workers. Nothing is uploaded to a server.
WebP vs JXL
What changes from WebP to JXL
Encoding: the WebP uses lossy VP8 coding or lossless VP8L; JXL uses lossy VarDCT or lossless modular coding; existing JPEGs can be repacked without loss, and the download is a JPEG XL encoded with libjxl compiled to WebAssembly, lossy at the quality you choose or lossless.
Bit depth: 8 bits per channel in the WebP; JXL allows 8 to 16 bits per channel, or floating point, and the JXL written here has 8 bits per channel.
Colour: RGB; lossy WebP stores colour at half resolution (4:2:0) in the WebP; JXL supports sRGB, Display P3, linear and other spaces described in the codestream, written here as 8-bit sRGB.
Transparency: the WebP stores it as a separate alpha plane, available in lossy as well as lossless files; the JXL keeps it as an extra channel in the codestream.
Animation: ANMF frame chunks, each with its own delay and blending; the JXL holds one image, so only the first frame is converted.
Metadata: the WebP can carry EXIF, XMP and ICC chunks; JXL can carry EXIF and XMP boxes in the container form, often stripped by encoders, but nothing is copied across.
About WebP
WebP is Google's web image format. It supports lossy and lossless compression, transparency and animation, and is typically 25 to 35 percent smaller than JPEG at the same visual quality.
A WebP is a RIFF file: 'RIFF', a length, 'WEBP', then chunks. A simple lossy file is one VP8 chunk and a lossless one is VP8L; the extended VP8X header announces alpha, animation, ICC, EXIF or XMP chunks.
WebP files usually come from websites, Chrome's Save image as, CDNs and Android apps.
About JXL
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.
When converting WebP to JXL makes sense
JXL is the better choice for archiving and future-proof high quality storage, while WebP suits images on websites and in apps.
JXL strengths: Excellent lossy and lossless compression; Progressive decoding and HDR; Huge image sizes. Drawbacks to weigh: Browser support is limited (Safari only by default); Few apps can open it yet.
Limitations
- A lossy WebP converted to another lossy format pays twice: detail VP8 already dropped stays gone, and the new encoder drops more.
- WebP images saved from websites are often already resized and compressed for the page, so the result cannot be sharper than that copy.
- Chrome and Firefox do not display JPEG XL by default, so it is not yet a format for websites; it suits archives and apps that support it.
- Lossless JPEG XL is usually smaller than PNG for the same pixels.
More conversions
Related tools
Convert JXL to WebP in your browser, ready for images on websites and in apps. Batch, private, no uploads.
Convert WebP to JPG in your browser, with transparency filled in a colour you pick. Batch, private, no uploads.
Convert WebP to PNG in your browser, ready for screenshots, logos, graphics and anything that needs transparency. Batch, private, no uploads.
Convert WebP to GIF in your browser, with the animation kept frame for frame. Batch, private, no uploads.
Convert JPG to JXL in your browser, ready for archiving and future-proof high quality storage. Batch, private, no uploads.
Shrink JPG, PNG, WebP, AVIF and GIF files with MozJPEG, OxiPNG and modern codecs, with a live before/after preview.
Resize to exact pixels, a percentage or a longest side, with Lanczos3 and Magic Kernel resampling. Batch ready.
Strip EXIF, GPS, XMP, IPTC and comments losslessly. Pixels are never re-encoded for JPG, PNG and WebP.
Frequently asked questions
Does converting WebP to JXL lose quality?
JXL is lossy, so detail the eye barely notices is discarded to save space. The WebP was lossy already, so keep the quality high to avoid stacking artefacts.
Is transparency kept in the JXL?
Yes. WebP stores it as a separate alpha plane, available in lossy as well as lossless files, and the JXL is written with an alpha channel, so transparent areas stay transparent.
Will my animated WebP stay animated?
No. JXL holds a single image, so only the first frame is kept. Convert to animated WebP, APNG or GIF to keep the motion, or export every frame with the GIF Frame Extractor.
Which apps open JXL files?
Safari 17+, macOS 14 and iOS 17, GIMP, Krita, ImageMagick and the libjxl tools. It opens in Safari 17 and later; Chrome and Firefox do not display it by default.
Are my images uploaded anywhere?
No. Processing happens inside your browser with WebAssembly and Web Workers. The site only downloads the app code and codecs; your files never leave your device. You can confirm this with the live upload counter on the tool, or in your browser's network panel.
Can I process many files at once?
Yes. Drop a whole selection or folder. Files are processed in parallel on several worker threads, each result can be downloaded on its own, and everything can be saved as one ZIP.
Is it free? Is there a file limit or watermark?
It is free with no account, no watermark and no daily limit. The only limit is your device's memory: very large images (over roughly 100 megapixels) may be refused to keep the tab from crashing.