What Is JPEG XL?
JPEG XL (file extension .jxl) is an image format standardized as ISO/IEC 18181 in 2022. It was developed by the JPEG committee (the same group behind the original JPEG) with the explicit goal of being a single format that replaces JPEG, PNG, GIF, and WebP simultaneously. The name "JPEG XL" stands for JPEG Extended Long-term, reflecting its ambition as the long-term successor to the original JPEG.
Unlike WebP (based on VP8) and AVIF (based on AV1), JPEG XL was designed from scratch as an image codec rather than adapted from a video codec. This purpose-built design gives it unique capabilities that video-derived formats cannot easily replicate.
Key Features of JPEG XL
Lossless JPEG Recompression
This is JPEG XL's most unique feature. JPEG XL can take an existing JPEG file and recompress it losslessly, producing a .jxl file that is 20-30% smaller with zero quality loss. The original JPEG can be perfectly reconstructed byte-for-byte from the JXL file. No other format can do this.
This matters enormously for the billions of existing JPEG images on the web. Converting a JPEG to WebP or AVIF is always a lossy re-encode that introduces additional quality degradation. JPEG XL can shrink those same files without any generational loss whatsoever.
Superior Lossy Compression
At lossy compression, JPEG XL is competitive with AVIF and superior to WebP:
| Format | Size vs JPEG (same quality) | Best At |
|---|---|---|
| WebP | 25-35% smaller | General web use, fast encoding |
| AVIF | ~50% smaller | Maximum compression, HDR |
| JPEG XL | ~60% smaller | High quality, progressive decode, versatility |
At high quality settings (where differences matter most for photography and e-commerce), JPEG XL often outperforms AVIF. The advantage is most pronounced at quality levels above q85 equivalent, exactly where professional and commercial images tend to be encoded.
Progressive Decoding
JPEG XL supports true progressive decoding, where the image loads in increasing quality passes. The browser can display a useful preview of the full image after receiving only 10-20% of the file data. This is similar to progressive JPEG but more efficient.
Neither WebP nor AVIF support progressive decoding. They are all-or-nothing: the browser must download the entire file before displaying anything. For large, high-quality images on slow connections, progressive decoding provides a dramatically better user experience.
HDR and Wide Gamut
Like AVIF, JPEG XL supports HDR (up to 32-bit floating point) and wide color gamuts including Display P3 and Rec. 2020. It also supports the Perceptual Quantizer (PQ) and Hybrid Log-Gamma (HLG) transfer functions used by HDR displays.
Animation
JPEG XL supports animation natively, with features comparable to APNG but with much better compression. Animated JPEG XL files can use lossy or lossless compression and support full alpha transparency.
Other Notable Features
- Transparency: Full alpha channel support in both lossy and lossless modes
- Multiple layers: Native support for layers and blend modes
- Metadata preservation: Full EXIF, XMP, and JUMBF metadata support
- Fast decoding: Designed for single-core and multi-core decoding; faster to decode than AVIF
- Encoding speed: Configurable speed/quality tradeoff; fast modes are comparable to WebP encoding speed
- No royalties: Royalty-free, like WebP and AVIF
Browser Support in 2026
Browser support is JPEG XL's biggest challenge and the primary reason it is not yet the default recommendation:
| Browser | JPEG XL Status (April 2026) |
|---|---|
| Safari (macOS/iOS) | Full support since Safari 17 (2023) |
| Chrome | Behind flag (chrome://flags/#enable-jxl); intent to ship announced |
| Firefox | Behind flag (image.jxl.enabled in about:config); under consideration |
| Edge | Follows Chrome; behind flag |
| Opera | Follows Chrome; behind flag |
| Samsung Internet | Not yet supported |
Safari is the only major browser with JPEG XL enabled by default. Chrome removed JXL support in Chrome 110 (2023) but reversed course and is actively working toward shipping it. As of early 2026, Chrome has re-enabled the flag and signaled intent to ship. Firefox is monitoring Chrome's decision and is expected to follow.
The practical implication: you cannot rely solely on JPEG XL for web delivery in 2026. You need fallbacks. However, the trajectory is clearly toward broad support, and early adopters who prepare JXL assets now will benefit as browsers enable support.
JPEG XL vs WebP vs AVIF
| Feature | WebP | AVIF | JPEG XL |
|---|---|---|---|
| Lossy compression | Good (25-35% < JPEG) | Excellent (~50% < JPEG) | Excellent (~60% < JPEG) |
| Lossless compression | Good | Good | Best in class |
| JPEG recompression | No | No | Yes (20-30% savings, lossless) |
| Progressive decoding | No | No | Yes |
| HDR / Wide gamut | No (8-bit sRGB only) | Yes (10/12-bit) | Yes (up to 32-bit float) |
| Animation | Mature | Less mature | Supported |
| Encoding speed | Fast | Slow | Configurable (fast to slow) |
| Decoding speed | Fast | Moderate | Fast |
| Browser support (2026) | 97%+ | 93%+ | Safari only (by default) |
| Royalty-free | Yes | Yes | Yes |
How to Use JPEG XL Today
Despite limited browser support, there are practical ways to use JPEG XL right now:
- Archival storage: Use JPEG XL's lossless JPEG recompression to shrink your JPEG photo library by 20-30% with zero quality loss. You can reconstruct the original JPEG at any time.
- Progressive enhancement: Serve JXL to Safari users and AVIF/WebP to others using the
<picture>element or CDN-based content negotiation. - Native apps: iOS and macOS apps get JXL support automatically through the system image frameworks.
- Preparation: Generate JXL versions of your image assets now so they are ready when Chrome ships support.
Working with JPEG XL in FastEdit
FastEdit supports JPEG XL decoding and encoding in the browser via its WebAssembly-based processing pipeline. You can open .jxl files, convert other formats to JPEG XL, and take advantage of the lossless JPEG recompression feature to shrink your existing JPEG files without quality loss. You can also compare JXL output against WebP and AVIF to see exactly how each format performs on your specific images. All processing happens locally in your browser.
The Future of JPEG XL
JPEG XL is technically the most capable image format available in 2026. It compresses better than WebP, matches or exceeds AVIF at high quality, and offers unique features like lossless JPEG recompression and progressive decoding that no other format can replicate. The only thing holding it back is browser support outside Safari.
If Chrome ships JPEG XL support by default (which current signals suggest is likely), the format landscape will shift dramatically. JPEG XL would become the single-format solution that eliminates the need for the AVIF-then-WebP-then-JPEG fallback chain. Watch this space.