Malamutes are substantially larger. Mals were bred to pull an extremely heavy load long way at a slow place. You want to move your whole village, you take a malamute team. Siberians were bred to pull a moderate load at a faster pace.

Malamutes tend to be dog aggressive, particularly to the same sex. Their temperment is in general more stand-offish than the typically outgoing husky.

A purebred malamute can not have blue eyes. They can come in any color as can a purebred Siberian. They are both double coated.

I have both in my yard.

Heyoka, my purebred mal, weighs 130 odd pounds. My biggest siberian weighs 65.

Muskwa is a purebred siberian.