JPEG XL vs WebP
JPEG XL is the better format. WebP is the more useful one. That contradiction is the entire comparison, and which side of it matters depends on one question: does the image need to open on someone else's computer?
by Robert Castillo · Published · updated
The verdict, up front
Publishing images on a website? Use WebP, or serve JPEG XL with WebP as the fallback. Every browser in use today renders WebP. JPEG XL is now on by default in Chrome 155, Firefox 158 and Safari 17, but Edge still doesn't show it, and nor does any browser that hasn't been updated. A better format that some of your visitors cannot see is not, on its own, a better format.
Storing, archiving or editing your own photos? Use JPEG XL. It compresses harder at the quality levels you'd actually keep photos at, it holds HDR and high bit depths that WebP simply discards, and it can re-pack your existing JPEG library losslessly — which WebP cannot do at all.
Feature by feature
| WebP | JPEG XL | |
|---|---|---|
| Released | 2010 | 2021–22 (ISO/IEC 18181) |
| Browser support | Universal | Chrome 155+, Firefox 158+, Safari 17+; not Edge |
| Compression at high quality | Good | Better |
| Compression at very low quality | Competitive | Competitive |
| Lossless mode | Yes | Yes, stronger |
| Bit depth | 8-bit only | Up to 32-bit float |
| HDR / wide gamut | No | Yes |
| Lossy chroma | 4:2:0 | Selectable, up to 4:4:4 |
| Maximum dimensions | 16 383 × 16 383 px | No practical limit |
| Progressive decoding | No | Yes |
| Re-packs existing JPEGs losslessly | No | Yes, ~20% smaller |
| Royalty-free | Yes | Yes |
A note on the numbers you'll see quoted
Search for this comparison and you will find confident claims that JPEG XL is "35% smaller than WebP", or 20%, or 50%. Treat all of them carefully, including any we could have put here.
Image compression results depend on the photograph, the quality target, the encoder version and the effort setting — and on how quality was matched between two formats, which is the part almost nobody states. A comparison at "quality 80" in each encoder is meaningless, because the two scales are unrelated. Done properly you need a perceptual metric and a corpus of images, and the honest output is a curve, not a headline percentage.
What is safe to say: at the quality levels people actually keep photographs at, JPEG XL is usually meaningfully smaller than WebP; in lossless mode the gap widens; and at aggressively low quality the two converge. If the exact number matters to you, the only answer worth having is the one from your images — so run a few of them through the converter and compare the file sizes yourself. It's free and nothing gets uploaded.
The one thing WebP cannot do at all
Everything above is a matter of degree. This one isn't.
JPEG XL can take an existing JPEG and re-pack it losslessly — roughly 20% smaller, with the original JPEG reconstructible byte for byte. Not "visually identical". The same file back.
For anyone with a photo library of tens of thousands of JPEGs, this is the single most useful thing either format does: about a fifth of the storage back, no quality decision to agonise over, and no lock-in, since you can always unpack to the original. Converting those JPEGs to WebP would mean re-compressing them — throwing away quality to save space, permanently. Try it on one of your own JPEGs and watch the size drop without touching a quality slider.
Which one should you pick?
Website images → WebP
Universal support, good compression, no fallback machinery to maintain. Since Chrome 155 switched JPEG XL on by default (6 October 2026), you can also serve JPEG XL first and keep WebP as the fallback for Edge and older browsers.
Photo archive → JPEG XL
Lossless JPEG re-packing, HDR preserved, better compression where it counts. You control the software that opens them.
Graphics & screenshots → JPEG XL
WebP's lossy mode is locked to 4:2:0 chroma, which smears coloured text and sharp edges. JPEG XL can keep full colour resolution.
Huge panoramas → JPEG XL
WebP stops at 16,383 pixels per side. Stitched panoramas and high-resolution scans hit that wall regularly.
Sending to someone → neither
Send a JPEG or PNG. Plenty of people still can't open a WebP either, let alone a .jxl.
Animation → either, carefully
Both support it, both are better than GIF, and neither is well supported by editing tools. For the web, WebP is the pragmatic pick.