Chrome 155 opens images JPEG XL without extensions or flags to activate manually: the release on the Stable channel for Windows, macOS and Linux brought with it the native decoding of files with extension .jxlincluding animations. Google has thus followed up on the commitment made at the beginning of 2026, after having declared the same format obsolete just three years earlier.
On a technical level, the declared profit is one 30 to 50% more efficient compression compared to traditional JPEG, to which lossless mode is added, support HDR and fine-grained progressive decoding. There is also lossless transcoding of old JPEGs, which allows you to lighten existing archives without going through destructive reconversion.
Mountain View places the ideal use case in high-fidelity photographic images and contexts where lossless compression is needed, not in kilobyte thumbnails. The format, standardized as ISO/IEC 18181, has existed since 2021 but has never seen mass diffusion.
The decoder rewritten in Rust, including SIMD
The decoding engine is called jxl-rs and abandons the C++ reference library in favor of Rust: Image decoders remain one of a browser’s most targeted attack surfaces, and automatic memory management cuts out out-of-bounds reads, heap overflows, and use-after-free at the root.
The problem was speed, because a language with stringent controls risks paying the price on vector instructions. The team has stabilized the functionality target_feature_11 of the compiler and built on top jxl_simdan abstraction layer inspired by the Highway library (originally developed for libjxl), achieving cross-platform optimizations without resorting to unsafe code. Fuzzing and automatic code review did not identify any memory bugs.
The acronym, it must be said, does not mean Extra Large: the X recalls the nomenclature of the JPEG standards published since 2000 (XT, XR,
As for the reason for the rethink, Google indicates the pressure from developers, which came through the Interop 2026 proposals and also ranked high in previous editions. The company’s invitation is explicit: “With the official arrival of JPEG XL in Chrome, the web becomes faster, richer and safer”, and the request is to insert JXL images and animations into the production pipelines while reporting any bugs.
The update is downloaded from the browser Settings, in the Help section and then About Google Chrome, with a final restart. It’s worth installing quickly regardless of format: this release brings an abnormal number of security fixes, some classified as critical.
Chrome knows how to read JXL, not write it. Coding remains the responsibility of those who publish, so the real test will be played on CDN, CMS and photo editing software: until that chain moves, support in the most used browser in the world remains an open door to an almost empty room.
