It may not be as widely used as lossy, but it does have valid uses that lossy just can’t substitute and the web needs to accomodate for. And the space savings offered by JPEG XL seem pretty great in that regard.

‘The average Web consumer’ may not need lossless, but a non-negligible minority very well might, hence why lossless should absolutely be on topic.

JPEG XL isn’t consistently better enough to justify it. If lossless is so important, maybe we should be campaigning for HALIC.

Isn’t HALIC proprietary?

JPEG XL is an open format with a libre reference implementation, usually compresses better than WebP/PNG, and supposedly has plenty of room for improvement still (in said implementation). Add to that its versatility in other areas and the fact that it seems to have generated widespread interest (much unlike WebP in its time, from what I recall), and I think campaigning for it makes perfect sense.

I can tell you that I don't care if the AI slop used in everyone's AI generated blog is lossy compressed. In fact, expecting it to be of such import that lossless is required is pretty farcical.

I'm active in many art communities on the web for whom being able to view and share lossless images are table stakes. Also many other communities for which being able to view and share lossless screen captures is fundamental.

I can accept a claim that JPEG-XL is not the best format for it, or that it is good, but not worth the complexity and extra surface area it introduces. I can not accept a claim that "lossless just isn't very useful on the web".

What percentage of the web is that 0.1% ? 0.01% ?

I think its correct to say a use case that is very niche on the web isn't super important to the web. Especially when there already exists a bunch of lossless formats. After all, the value proposition of jxl is to save some bytes. It would be different if the point was introducing images as a whole.

count .png-s in the web. There's a lot. And .jxl's lossless is much better than png's. Basically any image with sharp lines (screenshots, image of a button etc) or gradients should be lossless.

This is outdated thinking. AVIF is really good at sharp lines & gradients. https://hacks.mozilla.org/2026/08/intent-to-ship-jpeg-xl/#:~...

Not at lossless, though.

If you're counting by absolute numbers, 90% of the web is probably YouTube, Facebook, Instagram, Twitter, Bluesky, Reddit, TikTok and the other major silos. I don't think those should be able to define all the web technologies for everybody else.

> Especially when there already exists a bunch of lossless formats.

Sure, but I'm not defending JXL here in particular, just arguing against the point that lossless images are unimportant on the web.

Perhaps niche compared to the entire web, but we use lossless webp for gaussian splat data delivery for realtime rendering. (https://developer.playcanvas.com/user-manual/gaussian-splatt...).

Scenes often comprise gigabytes of lossless webp, some of which you can see at https://superspl.at.

We could get better compression using a custom encoder, however with webp the browser decodes off the main thread, copies the resulting data to GPU memory and caches the images for us. All very useful on the web!