FITS to JPC Converter
Processing entirely on your device — large files may take a moment.
Flexible Image Transport System and JPEG 2000 Code Stream exist for different jobs: 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. Convert photos to JPC for streaming pipelines, or JPC back to JPG/PNG for everyday viewing.
This converter runs entirely in your browser using WebAssembly — your files never leave your device, nothing is uploaded, and there are no watermarks, sign-ups or queues. Drop in several files at once to convert them as a batch.
How FITS compares to JPC
| FITS | JPC | |
|---|---|---|
| Compression | None (optionally Rice/GZIP) | Wavelet (lossy + lossless) |
| Transparency | Not supported | Supported |
| Animation | Not supported | Not supported |
| Metadata | Rich text header (WCS) | None (bare codestream) |
| Best for | Telescope frames, science data | Broadcast streams, archival pipelines |
How to convert FITS to JPC
- 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 JPC". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted JPC 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 JPC format
JPC is JPEG 2000 stripped to its bare codestream: the same wavelet-compressed image data as JP2, minus the container boxes that give JP2 its metadata, color profiles and file signature. Broadcast and archival systems that stream codestreams directly (rather than storing boxed files) work with JPC.
Because there is no container, JPC carries no thumbnail, no EXIF and no declared colorspace — players must probe the codestream header itself. Converting JPC into JP2 restores a full container; converting to JPG or PNG produces an instantly viewable copy.
+Strengths
- ✓Wavelet compression, better per-byte quality than JPG
- ✓True lossless mode available
- ✓Streamable — no container parsing needed
!Limitations
- −No metadata, color profile or thumbnail
- −Browsers cannot open it at all
Why convert FITS to JPC?
There is a concrete reason this conversion exists: Not display-ready JPC sidesteps that — Wavelet compression, better per-byte quality than JPG If that is your situation, the tool above settles it in seconds, entirely on your device.
Frequently asked questions
Is this FITS to JPC 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 JPC?
No — JPC 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.
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.
Can I convert several FITS files at once?
Yes — drop as many files as you like into the tool and they are converted in one batch. When more than one file comes out, everything is bundled into a ZIP for a single download.