Convert gd to pnm Online: gd2pnm

You can use Tom's Editor to easily convert images from
GD Library Image .GD to Portable aNy Map .PNM.
Tom's Editor is a free, online image manipulation and converter program.

Go to Tom's Editor

GD

GD Library Image is an image format with extension GD.

PNM

PNM images are uncompressed 24 bit RGB images. Can cannot store Alpha channel. PNM images come in 2 types: binary and text. Especially popular on Linux.