FITS Won't Open? Convert to JXL Instantly
Fast, instant FITS to JPEG XL conversion. No signup required. Just drop your .fits file and get .jxl in seconds.
Batch Settings
FITS-Dateien sind das Rückgrat der astronomischen Datenverarbeitung, komplex und reich an Informationen. Doch für die effiziente Archivierung, schnelle Vorschau oder die Einbindung in moderne Webanwendungen sind schlankere, fortschrittlichere Formate oft vorzuziehen. Hier kommt JPEG XL (JXL) ins Spiel: Es bietet überlegene Kompression bei gleichzeitig hoher Bildqualität und unterstützt eine breite Palette an Funktionen, die FITS-Daten zugänglicher machen. Unser Konverter ermöglicht Ihnen die nahtlose Umwandlung Ihrer FITS-Aufnahmen in das zukunftssichere JXL-Format. Profitieren Sie von reduzierten Dateigrößen ohne sichtbaren Qualitätsverlust und bereiten Sie Ihre wertvollen Daten optimal für die Weiterverarbeitung und Veröffentlichung vor. Dies ist besonders vorteilhaft in Umgebungen, wo Speicherplatz und Bandbreite kritische Faktoren darstellen.
- Archivierung wissenschaftlicher Aufnahmen
- Web-Integration von CAD-Modell-Renderings
- Effizienter Austausch großer Bilddaten in Ingenieurbüros
In Deutschland, Österreich und der Schweiz gewinnt die datenschutzkonforme Verarbeitung und Speicherung von Bilddaten zunehmend an Bedeutung. JXL bietet hier durch seine Effizienz Vorteile, die bei der Einhaltung strenger Datenschutzrichtlinien wie der DSGVO unterstützen können, indem es den Bedarf an Speicherressourcen minimiert.
About FITS to JPEG XL Conversion
Dealing with a FITS file that won't open on your device? You're not alone — FITS compatibility issues are one of the most common reasons people search for a file converter. FITS is a widely used file format.
The fix is simple: convert your FITS to JXL. JPEG XL is a next-generation format with both lossless and lossy modes, aiming to replace JPEG and PNG. This conversion lets you convert between formats quickly, solving the problem in seconds rather than hours of troubleshooting.
Converting FITS to JXL maintains high quality with CocoConvert's optimised encoder settings.
CocoConvert processes your FITS file on secure servers in Germany — upload, convert, download. Your files are encrypted via TLS and automatically deleted within 24 hours. No account needed, no software to install, and it works on any device with a browser.
This conversion is ideal when you When you need a JXL file.
The conversion engine behind CocoConvert uses FFmpeg, Sharp, and qpdf — the same open-source libraries trusted by Netflix, YouTube, and enterprise platforms. Pro users can batch convert up to 100 files at once.
How to Convert FITS to JPEG XL
- 1
Add your FITS file
Drag and drop your .fits file into the converter, or tap "Browse" to pick it from your device. Multiple files are supported for batch processing.
- 2
Pick JXL output
Select .jxl as the target format. CocoConvert automatically applies the best quality settings for this conversion.
- 3
Start conversion
Hit the Convert button. The image engine processes your file server-side — no CPU drain on your device.
- 4
Save your file
Once done, download your .jxl file. For batch jobs, download all at once as a zip.
What Happens When You Convert FITS to JPEG XL
Your FITS file is decoded and re-encoded as JXL.
Your FITS file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in JXL format
The converted file is ready for download
Format Comparison
FITS
.fits file
| Extension | .fits |
| MIME Type | image/fits |
| Category | Image |
JPEG XL
.jxl file
| Extension | .jxl |
| MIME Type | image/jxl |
| Category | Image |
Should You Convert FITS to JPEG XL?
When to Convert
- ✓When you need a JXL file
Frequently Asked Questions
Why won't my FITS file open?
FITS files may not open if your device lacks the right codec or application. Converting to JXL — a more widely supported format — usually resolves this. JPEG XL is a next-generation format with both lossless and lossy modes, aiming to replace JPEG and PNG.
Is it safe to convert FITS to JXL online?
Yes. CocoConvert encrypts your file via TLS, processes it on isolated servers in Germany, and permanently deletes it within 24 hours. Your files are never shared or analysed.
Will I lose quality converting FITS to JXL?
Converting FITS to JXL maintains high quality with CocoConvert's optimised encoder settings. CocoConvert uses high-quality encoder defaults to preserve as much fidelity as possible.
How large can my FITS file be?
Free users can convert files up to 250 MB each. Pro users get a 5 GB limit per file, and Business API users have custom limits.
Can I convert FITS to JXL on my phone?
Absolutely. CocoConvert works in any modern browser — iOS Safari, Android Chrome, and all desktop browsers. No app required.
Versions are pinned in our worker Dockerfile and re-built via CI on every change.