BMP to PCX Converter
Convert BMP to PCX in your browser. BMP files usually come from Windows Paint, legacy Windows programs, embedded displays and some scanners; PCX is the better fit for DOS-era software, retro games and old fax or scanner tools. You get a run-length encoded PCX: 8-bit indexed when the image has 256 colours or fewer, otherwise 24-bit RGB. Nothing is uploaded.
- Processed locally
- No upload, no wait
- No sign-up
- No watermark
Drop images here
or choose files · paste with Ctrl/⌘ V
BMP expected · other image formats also work
How to use BMP to PCX
- 1
Add your BMP files: drop them here, choose them, or paste from the clipboard.
- 2
Pick the colour that replaces transparent areas, since PCX has none.
- 3
Click Convert. Each file is decoded and encoded in a background thread on this device.
- 4
Download the .pcx files one at a time or together as a ZIP.
Why use Aback Images for bmp to pcx
Where the PCX goes next
PCX opens in GIMP, IrfanView, XnView, ImageMagick, Paint Shop Pro and DOSBox-era tools.
PCX next to BMP
Both sides are lossless, so the size depends on how well the PCX encoder handles this picture compared with the BMP's usually none; RLE for some 4 and 8-bit files.
Written without a lossy pass
The PCX is written losslessly, so the pixels decoded from the BMP arrive unchanged.
Processed on your device
Your images are decoded, edited and encoded inside this browser tab by Web Workers. Nothing is uploaded to a server.
BMP vs PCX
What changes from BMP to PCX
Encoding: the BMP uses usually none; RLE for some 4 and 8-bit files; PCX uses byte-wise run-length encoding, and the download is a run-length encoded PCX: 8-bit indexed when the image has 256 colours or fewer, otherwise 24-bit RGB.
Bit depth: 1, 4, 8, 16, 24 or 32 bits per pixel in the BMP; PCX allows 1, 2, 4 or 8 bits per pixel with a palette, or 24-bit as three 8-bit planes, and the PCX written here has 8-bit indexed or 24-bit RGB.
Colour: RGB or an indexed palette in the BMP; PCX supports a 16 or 256-colour palette, or 24-bit RGB, written here as 8-bit sRGB.
Transparency: the BMP stores it as an optional fourth byte in 32-bit files, which many programs ignore; the PCX has none, so transparent areas are filled with the colour you choose.
Metadata: the BMP can carry nothing beyond the header's resolution fields (and a colour profile in rare V5 headers); PCX can carry only a 128-byte header with the resolution, but nothing is copied across.
About BMP
BMP stores raw, uncompressed pixels. Files are huge but trivially simple, which is why some legacy Windows software, embedded displays and printers still ask for it.
A BMP is a 14-byte file header ('BM' and the offset to the pixels), a DIB header (40 bytes, or 108 and 124 bytes in the V4 and V5 versions that add colour masks and alpha), an optional palette, then pixel rows padded to 4 bytes and normally stored bottom-up.
BMP files usually come from Windows Paint, legacy Windows programs, embedded displays and some scanners.
About PCX
PCX is the image format of ZSoft's PC Paintbrush, the standard for DOS paint programs, scanners and games before GIF and BMP took over. It compresses with a simple run-length scheme.
A PCX file has a 128-byte header (the byte 0x0A, version, encoding, bits per pixel, image window, DPI, a 16-colour palette and the number of colour planes), then RLE-compressed scanlines; 256-colour files end with the byte 0x0C and a 768-byte palette.
When converting BMP to PCX makes sense
PCX is the better choice for DOS-era software, retro games and old fax or scanner tools, while BMP suits legacy software and embedded systems that require it.
PCX strengths: Read by most legacy and modern viewers; Simple, lossless run-length compression. Drawbacks to weigh: Poor compression for photographs; No transparency; Obsolete outside retro software.
Limitations
- BMP stores nearly every pixel literally, so almost any compressed target is several times smaller.
- A 32-bit BMP can carry an alpha byte that most programs ignore; if the image suddenly gains transparent areas after converting, that byte was set.
- PCX's run-length compression suits flat-colour art; photographs barely shrink.
- Transparency is flattened onto the background colour, since PCX has no alpha channel.
More conversions
Related tools
Convert PCX to BMP in your browser, ready for legacy software and embedded systems that require it. Batch, private, no uploads.
Convert BMP to JPG in your browser, with transparency filled in a colour you pick. Batch, private, no uploads.
Shrink JPG, PNG, WebP, AVIF and GIF files with MozJPEG, OxiPNG and modern codecs, with a live before/after preview.
Resize to exact pixels, a percentage or a longest side, with Lanczos3 and Magic Kernel resampling. Batch ready.
Strip EXIF, GPS, XMP, IPTC and comments losslessly. Pixels are never re-encoded for JPG, PNG and WebP.
Convert between 34 image formats in bulk: HEIC, WebP, AVIF, JPEG XL, PNG, JPG, GIF, TIFF, SVG, ICO, PSD, RAW and more.
Frequently asked questions
Does converting BMP to PCX lose quality?
PCX is written losslessly, so the pixels are stored exactly as decoded.
What happens to transparency when converting BMP to PCX?
BMP stores transparency as an optional fourth byte in 32-bit files, which many programs ignore. PCX has no alpha channel, so transparent pixels are composited onto a solid colour, white unless you pick another. To keep transparency, convert to PNG, WebP or AVIF instead.
Which apps open PCX files?
GIMP, IrfanView, XnView, ImageMagick, Paint Shop Pro and DOSBox-era tools. It does not open in web browsers.
Are my images uploaded anywhere?
No. Processing happens inside your browser with WebAssembly and Web Workers. The site only downloads the app code and codecs; your files never leave your device. You can confirm this with the live upload counter on the tool, or in your browser's network panel.
Can I process many files at once?
Yes. Drop a whole selection or folder. Files are processed in parallel on several worker threads, each result can be downloaded on its own, and everything can be saved as one ZIP.
Is it free? Is there a file limit or watermark?
It is free with no account, no watermark and no daily limit. The only limit is your device's memory: very large images (over roughly 100 megapixels) may be refused to keep the tab from crashing.