Open .JXL files online
A .jxl file is an image in JPEG XL — the still-image codec standardized as ISO/IEC 18181 in 2021, designed to replace both JPEG (better compression, lossless JPEG recompression) and JPEG 2000 (which it beat in the standardization run-off). The browser story just flipped: Chrome 155, released October 6, 2026, decodes JPEG XL natively on desktop after the format's famous five-year detour (Chrome shipped it experimentally in 2020, removed it in 2021, and reversed course); Safari has decoded it since version 17 in 2023. Firefox has not shipped it yet — version 157, expected around November 2026, is slated to close the gap.
ZipTool opens .jxl files entirely in your browser and picks the decode path honestly: on Chrome 155+ and Safari the browser's own decoder renders the image (zero download); everywhere else a WebAssembly engine (~0.8 MB, fetched once from this site's own domain and cached) does the full decode — with a visible notice telling you which path you are on. Your image never leaves your device on either path.
What is a `.jxl` file?
JPEG XL arrives in two file shapes, and the viewer reads both: a bare codestream starting with the marker bytes FF 0A (what the reference cjxl encoder writes by default — JPEG's own SOI marker is FF D8, so the two never collide), or a small ISOBMFF container whose 12-byte signature box spells out size 0x0C, JXL, and the sync bytes 0D 0A 87 0A — the container shape carries EXIF metadata and more than one codestream. The tool's byte sniffing accepts exactly these two magics.
The capability set is the format's pitch: roughly 25–60% better compression than the original JPEG at equal visual quality, true lossless mode, 10/12-bit color with HDR (PQ/HLG), alpha transparency, animation — and one trick nothing else has: lossless recompression of an existing JPEG, shrinking it about 20% while guaranteeing the exact original bytes come back on decode. That is why archival tools adopted JXL early: it is the only format that can make JPEGs smaller without touching their bits.
MIME type: image/jxl. Honest limits: this viewer renders a still image — an animated JXL shows its first frame, and an HDR file is tone-mapped to standard 8-bit sRGB. EXIF from container files is read for the Info panel, but it does not survive a JPG export. On browsers without native decode the first open fetches the ~0.8 MB engine once, then it is cached; converting a whole folder to JPG is the JXL to JPG batch.
- Opening .jxl photos on a machine whose image viewers predate the codec
- Previewing JPEG XL images inside a zip or archive without extracting first
- Checking what a mystery .jxl actually is — dimensions, EXIF, animation flag
- Converting JPEG XL to universally-openable JPG — the viewer's Download button or the /jxl-to-jpg batch
How to open a `.jxl` online
Open ZipTool in a new tab, then drop your .jxl onto the page — or click to browse for it, or paste a URL. The file opens in the JPEG XL viewer — your browser's own decoder on Chrome 155+ and Safari 17+, a built-in WebAssembly engine everywhere else (it says which, visibly), read entirely on your device.
- Drag your
.jxlonto the page — or click to browse, or paste a URL. - It opens immediately in the JPEG XL viewer — your browser's own decoder on Chrome 155+ and Safari 17+, a built-in WebAssembly engine everywhere else (it says which, visibly). No install, no sign-up.
- Read, search, or copy it. Your file never leaves your browser.
Open `.jxl` without uploading
Most "open jxl online" sites work by uploading your file to a server and processing it there. ZipTool does the opposite: it loads its parser once, then reads your .jxl locally in the browser tab. The contents stay on your device.
You can prove that in seconds. Open the page, press F12 for DevTools, switch to the Network tab, and open your file — no request carrying the file's contents is sent. You can also turn off Wi-Fi after the page loads and the file still opens. See security and privacy for the full picture.
Frequently asked questions
Does Chrome support JPEG XL now?
Yes. Chrome 155 — stable since October 6, 2026 — decodes JPEG XL natively on desktop (Android follows later), after the format's 2020 ship / 2021 removal / 2026 return arc. Safari 17+ has decoded it since 2023, and Firefox 157 (expected ~November 2026) is slated to complete the set. On this page your browser's native decoder is used when present, and the WebAssembly engine only when it isn't — a visible notice says which.
How do I open a .jxl file online?
Drag the .jxl onto the page (or click to browse, or paste a URL). It opens at full resolution with zoom, and the status bar offers a Download .jpg of the decoded pixels. If the image sits in a zip, drop the zip: the file tree opens, click the image, and it decodes straight from inside the archive.
Do you upload my .jxl file?
No. The decode runs in the page — your browser natively on Chrome 155+/Safari 17+, or the WebAssembly engine fetched once from this site's own domain elsewhere. No request ever carries your image: press F12 → Network and watch, or go offline after the page loads and the image still opens.
Can I convert a .jxl to JPG?
Yes — the viewer's Download .jpg button exports the full decode, and the JXL to JPG page batch-converts a whole folder (up to 50 per run) into one zip. EXIF and GPS do not survive the JPG re-encode, which for sharing is usually a privacy plus.
JPEG XL vs AVIF — which is this file?
They are different codecs with overlapping goals: AVIF (AV1) reached browsers in 2020–2023 and enjoys broad phone hardware decode; JPEG XL compresses better at high quality, supports progressive rendering, and uniquely losslessly recompresses existing JPEGs. The sniff is unambiguous — a .jxl starts FF 0A or carries the JXL signature box, an .avif declares the avif brand in its ftyp box — so a renamed file never confuses the routing. AVIF opens in the regular image viewer (open .avif online); JPEG XL opens here.