OrbConvert converts your image files online. Amongst many others, we support PNG, JPG, JPEG, WEBP, GIF, SVG and TIFF. You can use the options to control image resolution, quality and file size.
From
Portable GrayMap
The Netpbm grey-scale format — one channel, uncompressed. Colour information is discarded, not converted.
All PGM conversionsTo
Portable BitMap
The Netpbm one-bit format: every pixel is black or white, with no greys and no colour. Useful for masks and line art, unusable for photographs.
All PBM conversions