PCX to FITS Converter
Processing entirely on your device — large files may take a moment.
ZSoft Paintbrush PCX and Flexible Image Transport System exist for different jobs: PCX was THE DOS-era image format: ZSoft Paintbrush's RLE-compressed raster that every 1990s game, scanner and clipart CD shipped in. Simple enough that its spec fits on one page. Convert FITS frames to PNG or JPG to preview telescope data, or pack them into a ZIP for sharing.
Because the whole conversion happens on your device, it is instant, unlimited and genuinely private — no accounts, no watermarks, no files on anyone's server. Multiple files are converted in one go.
How to convert PCX to FITS
- 1
Select your files
Drag & drop your PCX 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 FITS". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted FITS file individually, or grab everything at once as a ZIP archive.
About the PCX format
PCX was the image format of the DOS decade: ZSoft Paintbrush's run-length-encoded raster that every scanner, game and clipart CD adopted because it was published, simple and fast on 286 hardware. The header is a fixed 128 bytes, the palette hides in the final 769, and the whole file can be decoded by one while-loop.
Retro gaming archives and 90s clipart collections are full of PCX files. Converting them to PNG or JPG finally makes them viewable — the pixels were always fine, the container was just ancient.
+Strengths
- ✓Decoded by a single RLE loop — no dependencies
- ✓Ubiquitous in DOS-era archives
- ✓Supports paletted and 24-bit variants
!Limitations
- −Effectively dead since Windows 95
- −Rows padded — some files have alignment quirks
- −256-color ceiling for most real-world files
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
Why convert PCX to FITS?
Think of it as moving your file to the container that fits the job. Effectively dead since Windows 95 FITS works differently: Self-documenting science headers If any of that sounds like your task, run the conversion — it takes seconds and nothing leaves your device.
Frequently asked questions
Is this PCX to FITS 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 PCX to FITS?
No — FITS is a lossless format, so every pixel of the converted image matches your original PCX file. You can also adjust the quality/size balance before converting when the target format supports compression.
Will transparent areas survive the conversion to FITS?
Transparency is kept whenever FITS 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 PCX files matters (camera model, GPS, timestamps), keep the original file as the master and treat the converted copy as the shareable version.