FITS to JPT Converter
Processing entirely on your device — large files may take a moment.
Convert JPT images exactly like JP2. If your files are still in FITS format, this page is the shortcut: FITS (Flexible Image Transport System) is the data format of professional astronomy — every image carries a human-readable header with telescope, exposure and world coordinates alongside the raw pixel data.
iLoveConverter processes everything locally on your computer, which makes it private and fast: no upload wait, no server storage, no limits. Add as many files as you like — batch conversion is built in.
How FITS compares to JPT
| FITS | JPT | |
|---|---|---|
| Compression | None (optionally Rice/GZIP) | Wavelet (lossy + lossless) |
| Transparency | Not supported | Supported |
| Animation | Not supported | Not supported (MJ2 is separate) |
| Metadata | Rich text header (WCS) | XML boxes (EXIF/GPS) |
| Best for | Telescope frames, science data | Archives, medical, cinema |
How to convert FITS to JPT
- 1
Select your files
Drag & drop your FITS files onto the area above, or click to browse. You can add multiple files at once for batch conversion.
- 2
Convert instantly
Click "Convert to JPT". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted JPT file individually, or grab everything at once as a ZIP archive.
About the FITS format
FITS (Flexible Image Transport System) has carried professional astronomy data since 1981: every file opens with a plain-text header that records telescope, instrument, exposure, filters and world coordinates, followed by raw pixel arrays — often 16-bit or float, sometimes data cubes.
Values can be negative or far above display range, so FITS never looks right in a photo viewer. Converting to PNG applies a simple scaling pass that reveals the nebula or galaxy in the numbers — good for previews, while science pipelines keep the original.
+Strengths
- ✓Self-documenting science headers
- ✓High bit depth (16/32-bit, float)
- ✓The standard of every observatory
!Limitations
- −Not display-ready
- −Files are large and uncompressed
About the JPT format
JPEG 2000 (JP2) replaced JPG's DCT blocks with wavelet transforms: at the same bitrate it shows fewer blocky artifacts, and its lossless mode compresses better than JPG ever could. It was the format of early digital cinema and remains common in archives, medical systems and geospatial pipelines.
Browser support never arrived — Chrome, Firefox and Safari all skip it — so a JP2 file is often invisible on the web. Converting JP2 to JPG or PNG makes archival material viewable anywhere; converting the other way gives long-term storage better compression.
+Strengths
- ✓True lossless mode
- ✓Better quality per byte than JPG
- ✓ROI / progressive decoding built in
!Limitations
- −No browser support
- −Slow to encode compared to JPG
Why convert FITS to JPT?
Think of it as moving your file to the container that fits the job. Not display-ready JPT works differently: True lossless mode If any of that sounds like your task, run the conversion — it takes seconds and nothing leaves your device.
Frequently asked questions
Is this FITS to JPT converter really free?
Yes — completely free, with no sign-up, no watermark and no daily conversion limits. The site is supported by advertising.
Are my files uploaded to a server?
No. The conversion runs entirely inside your browser using WebAssembly, so your files never leave your device — that is what makes it instant and private.
Does it work on Windows, Mac, iPhone and Android?
Yes. Anything with a modern browser works: Windows, macOS, Linux, Android and iOS. No software installation is required.
Will I lose quality converting FITS to JPT?
No — JPT is a lossless format, so every pixel of the converted image matches your original FITS file. You can also adjust the quality/size balance before converting when the target format supports compression.
Will transparent areas survive the conversion to JPT?
Transparency is kept whenever JPT actually supports an alpha channel. If the target format has none (like JPG), transparent areas are flattened onto a white background — that is a property of the format, not of this tool.
What happens to EXIF data and other metadata?
Conversions here re-encode the image, and re-encoding generally does not carry the original metadata over. If the EXIF data of your FITS files matters (camera model, GPS, timestamps), keep the original file as the master and treat the converted copy as the shareable version.