JPEG XL: The Image Format That Could Finally Replace JPEG

Let's be honest: JPEG has overstayed its welcome.

Created in 1992, JPEG became the universal image format because it worked. Compressed photos to reasonable sizes, looked decent, played nice with every device. But three decades later, we're still using the same compression algorithm from the floppy disk era to serve 4K photos on fiber internet.

The replacement attempts have been... messy. WebP showed promise but never quite took over. AVIF is technically superior but complicated. JPEG 2000 flopped. And then there's JPEG XL.

Here's why it might actually succeed where others failed.

What Makes JPEG XL Different

JPEG XL (JXL for short) was designed by the same committee that gave us JPEG—the Joint Photographic Experts Group. They learned from past mistakes and built something genuinely interesting.

The elevator pitch: 40-60% smaller files than JPEG at the same quality, with modern features like HDR, animation, and lossless compression all in one format.

But the real killer feature? Lossless transcoding from existing JPEGs.

Take any JPEG file. Convert it to JPEG XL. The file shrinks by ~20% with zero quality loss. Then you can convert it back to the original JPEG bit-for-bit. No other modern format can do this.

This matters because the web has billions of existing JPEG images. Being able to shrink them without sacrificing compatibility is a massive advantage. You can serve JPEG XL to modern browsers and fall back to the original JPEG for older ones—without storing two completely different files.

The Numbers: How Much Better Is It Really?

Let's talk compression. Because honestly, that's what matters most.

Independent tests (CloudFlare, Google, and academic studies) consistently show:

• vs JPEG: 40-60% smaller at equivalent quality
• vs WebP: 20-30% smaller
• vs AVIF: Comparable (slightly better for some image types, slightly worse for others)
• vs PNG (lossless): 35-50% smaller

A typical 500KB JPEG photo might become 200-300KB as JPEG XL. That adds up when you're serving millions of images.

But compression isn't the only story. JPEG XL decodes faster than JPEG on modern hardware because it was designed for parallel processing. A 12MP photo decodes in ~5ms vs ~15ms for JPEG (on a typical 2025 smartphone). That might sound trivial, but it means smoother scrolling on image-heavy sites.

The Browser Support Problem (And Why It's Getting Better)

Here's where things get messy.

Chrome had JPEG XL support in 2021. They shipped it as an experimental flag. Then in 2022, they removed it entirely, citing "insufficient interest" and "not enough benefits over existing formats."

The backlash was immediate. Photographers, web developers, and archivists all called it short-sighted. But Chrome stuck to their decision (likely because Google was already pushing WebP and didn't want to fragment their strategy).

As of April 2026, here's the support landscape:

• Safari: Full support since Safari 17.2 (late 2025)
• Firefox: Enabled by default since version 124 (early 2026)
• Chrome/Edge: Still no native support, but re-implementation is under discussion
• Native apps: iOS and Android both support it in system image libraries

So... it's not universal yet. But momentum is building.

And honestly? You don't need 100% browser support to start using it. Just use progressive enhancement—serve JPEG XL to supporting browsers and fall back to JPEG for the rest. Tools like KokoConvert's image converter make it easy to create multiple versions of the same image for this exact workflow.

Beyond File Size: What Else JPEG XL Brings

Smaller files are great, but JPEG XL has features that make it genuinely future-proof:

1. One format to rule them all

JPEG XL handles photos, graphics, screenshots, and animations in one format. No more choosing between JPEG (photos), PNG (graphics), and GIF/WebP (animation). It does all of it. With alpha transparency. And HDR. And 16-bit color depth.

2. Progressive decoding that actually works

Unlike JPEG's clunky progressive mode, JPEG XL streams beautifully. You see a low-res preview almost instantly, then it refines as more data arrives. Great for slow connections.

3. Region-of-interest encoding

You can mark parts of an image as "important" (like faces) and JPEG XL will allocate more bits there while compressing backgrounds more aggressively. This is subtle but powerful for portraits.

4. Lossless and lossy in the same file

Want the main image lossy-compressed but the alpha channel lossless? JPEG XL can do that. Weird flex, but useful for certain workflows (like product photos on transparent backgrounds).

When Should You Actually Use JPEG XL?

Look, I'm not saying you should convert your entire photo library tomorrow. But there are smart places to start:

Use JPEG XL if:

• You're building a new site and can implement modern image serving strategies
• Your bandwidth costs are high (image-heavy blogs, portfolios, e-commerce)
• You care about mobile performance (smaller files = faster loads on cellular)
• You're archiving photos long-term (lossless transcoding preserves originals)
• You want to reduce CDN costs without sacrificing quality

Stick with JPEG/PNG if:

• Your audience is mostly on older browsers (pre-2025)
• You need guaranteed email attachment compatibility
• Your CMS or tools don't support JPEG XL yet
• You're not ready to implement fallback strategies

The sweet spot right now? Serving JPEG XL with JPEG fallbacks. Use the <picture> element to offer JPEG XL first, then fall back to JPEG for unsupported browsers. Best of both worlds.

How to Start Using JPEG XL Today

Okay, so you're convinced. Here's the practical stuff.

Desktop tools:

• GIMP 2.10.32+ has native JPEG XL export
• ImageMagick 7.1+ supports it via command line (magick input.jpg output.jxl)
• Photoshop needs a plugin (search "JPEG XL Photoshop plugin" on GitHub)
• XnView and other image viewers added support in 2024-2025

Browser-based conversion:

If you don't want to install anything, online image converters like KokoConvert handle JPEG XL encoding and decoding entirely in your browser. Upload a JPEG, download a JXL file. No server upload needed (privacy win).

Batch conversion:

For converting hundreds of images, use ImageMagick's mogrify command or tools like batch image compressors that now include JPEG XL as an output option.

The Real Question: Will It Actually Replace JPEG?

Honestly? Maybe.

JPEG XL has real technical advantages. But so did JPEG 2000, and look how that turned out. Format wars aren't won by specs—they're won by adoption.

What JPEG XL has going for it:

• Apple and Mozilla are on board (Safari + Firefox = significant user base)
• Backward compatibility with existing JPEGs makes migration painless
• The archival community really wants this (long-term preservation matters)
• CDN providers are starting to support it (CloudFlare, Fastly)

What's working against it:

• Chrome's resistance (though that could change)
• AVIF already has momentum in some circles
• WebP is "good enough" for many use cases
• Inertia is powerful—people hate migrating

My take? JPEG XL will become the preferred format for new projects and high-quality archival work, but JPEG will stick around for legacy compatibility for another decade. Kind of like how MP3 is technically obsolete but still everywhere.

The web doesn't do clean transitions. It does slow, messy coexistence.

What to Do Right Now

If you're building something new, experiment with JPEG XL. See how it performs on your images. Test browser support among your users. Implement fallbacks.

If you're maintaining an existing site, don't rush. But start thinking about it. JPEG XL support is growing, and when Chrome eventually re-implements it (and they probably will, eventually), you'll want to be ready.

And if you're just a regular person taking photos? Keep shooting JPEGs. Your phone will handle the transition when the time comes. But know that when you look at your photo library in 2030, there's a decent chance it'll be full of .jxl files instead of .jpg.

JPEG had a good run. JPEG XL might just be what finally lets us move on.