How to convert PGM to BMP
- Add your .PGM file - drop it in the box above or click to browse.
- Convert it to .BMP in a few seconds.
- Download your new .BMP file.
What to expect
- No quality loss for standard 8-bit files - both formats are uncompressed, so every gray value is copied exactly.
- 16-bit PGM files (Maxval above 255) are scaled to 8-bit when writing BMP; use PNG or TIFF if you need to preserve 16-bit depth.
- BMP is slightly larger than PGM because it includes a file header and a 256-entry grayscale palette (~1 KB overhead).
Frequently asked questions
Does converting PGM to BMP change the image quality?
Not for 8-bit files - both formats are uncompressed and pixel values are copied exactly, so the visual result is identical.
Can I convert a 16-bit PGM to BMP?
Standard BMP does not support 16-bit grayscale; tools like ImageMagick will automatically reduce the bit depth to 8-bit. Use PNG or TIFF to retain 16-bit data.
Why is my BMP larger than the original PGM?
BMP adds a file header and a 256-entry grayscale palette; for large images the overhead is small, but BMP is always slightly bigger than the equivalent PGM.
Is BMP a good long-term format for grayscale images?
It works, but PNG is usually the better choice - same lossless quality, smaller files, and broader support across platforms.
