Drop Sun Raster (.ras) files here
Or choose files from your device. Everything is converted in your browser; nothing is uploaded.
How to convert a Sun Raster file to PNG
- Drop one or more
.rasfiles into the box above, or choose them from your device. Files ending in.ras.gzare unzipped automatically. - Check the preview. If reds and blues look swapped, tick Swap red and blue.
- Pick a PNG size. 1× keeps the original pixel dimensions; larger sizes enlarge each pixel into a crisp square.
- Download each PNG on its own, or download every converted file at once as a ZIP.
What is a Sun Raster file?
Sun Raster is a bitmap format created by Sun Microsystems for its SunOS and Solaris workstations. It was the standard screenshot and image format on Sun machines through the late 1980s and 1990s, so you'll find it in old research archives, CAD and scientific visualization output, and early UNIX software. Tools like ImageMagick, netpbm and xv can still write it.
The file is simple: a 32-byte header with the width, height and bit depth, an optional color map, then the pixel rows. Some files compress the rows with a basic run-length encoding. Modern browsers and image editors don't open the format, so converting to PNG is the easiest way to view or reuse these images.
Supported Sun Raster variants
| Bit depth | What it holds | How it converts |
|---|---|---|
| 1-bit | Black and white | Black and white, or two colors from the file's color map |
| 2, 4 and 8-bit | Indexed color or grayscale | Colors from the color map; grayscale when the file has none |
| 24-bit | Truecolor (BGR or RGB order) | Full color |
| 32-bit | Truecolor plus an extra byte | Full color; the extra byte becomes transparency when it holds real alpha values |
Both uncompressed files (standard, old and RGB types) and run-length encoded files (type 2, often called byte-encoded) are supported. Files saved in little-endian byte order by some non-Sun tools are detected and read as well.
Sun Raster converter FAQ
Are my files uploaded anywhere?
No. The files are read and converted by JavaScript running in your own browser. Nothing is sent to a server.
Does it support RLE-compressed Sun Raster files?
Yes. Files using Sun's run-length encoding (type 2) are decompressed automatically. The file card shows whether a file was compressed.
Why do the colors look wrong, with blue skies turning orange?
Sun Raster normally stores 24-bit and 32-bit pixels in blue-green-red order, but some programs wrote red-green-blue without marking the file that way. Tick Swap red and blue and every preview updates instantly.
Is transparency preserved?
A 32-bit Sun Raster file has one extra byte per pixel. Some programs store transparency there and others leave it empty. The converter checks the values and uses them as transparency only when they look like real alpha data. You can override this with the 32-bit extra byte setting.
Which file extensions does it accept?
The common ones are .ras, .sun, .rs and .rast, plus .im1, .im8, .im24 and .im32, where the number is the bit depth. The converter identifies files by their contents, so an unusual extension doesn't matter.
My file ends in .ras.Z. Can I convert it?
Files ending in .Z use the old UNIX compress format, which browsers can't unpack. Extract it first with 7-Zip, The Unarchiver or uncompress, then convert the .ras file inside. Files ending in .gz work directly.
Can I convert many files at once?
Yes. Drop or select as many files as you like, then use Download all as ZIP to save every PNG in one archive.
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