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
Bitmap
Stores every pixel uncompressed — simple and readable by old Windows software, but large. Transparency is not supported.
All BMP conversions