Your best option for finding compatible playmates for your dog is to identify your dog’s play style and select dogs of similar size, energy level, and play style preference.
Size matters. No doubt there are dogs of significant size disparity who can play well together, but as a general rule, it’s wise to keep the difference in the realm of 25 pounds or less. A playful dog can easily injure a little dog, even without intent to do harm, simply by running over or jumping on the smaller dog. Of even greater concern is a phenomenon known as predatory drift in which something from a dog’s evolutionary past triggers the larger dog’s brain to perceive the smaller dog as a prey object – a bunny or squirrel – instead of the canine pal he’s played happily with for months or years. Often the trigger is the smaller dog running, yelping, or squealing. The bigger dog gives chase, and tragedy ensues.
For more ideas and advice on the best ways to play with your dog and the benefits to both you and your dog, purchase Pat Miller’s book, Play With Your Dog.