First of all both of them are large in size around 28 to 34 inches, have square bodies, rectangular head with a deep muzzle. Ears are high set and cropped. Necks are muscular and legs are straight. Bred originally for tracking, Scooby Doo was a formidable tracker. The ferociousness of the Great Dane was bred out and has a very gentle personality.  Now, with their strength to knock you over when they run at fast speeds, just like Scooby running away from a Ghost. Although they share many attributes, the coat color of Scooby is not available in reality.