Convert hdr to pnm Online: hdr2pnm

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

Go to Tom's Editor

HDR

Radiance RGBE image is an image format with extension HDR.

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.