Dogs do not sweat in the same way we humans do. When a human being’s body temperature builds up, either because he or she is in a hot environmental setting or because he or she has been exercising or working a great deal, then he or she begins to perspire. When people sweat, it is quite obvious. Everybody perspires, although others do more so than some. For some human beings their sweat is only visible under their arms and on their brows, while other people seem to sweat almost everywhere.
A dog’s skin is a bit different, which is why you have never seen a dog with sweaty underarms. Most of the dog’s sweat glands are actually located around its foot pads.