Reward-based training is the approach we recommend, and it runs on food. The catch is that treats add up fast, and the most common side effect of enthusiastic training is a chubbier dog. The widely used veterinary guideline is simple: treats should make up no more than about 10 percent of your dog's daily calories, and you subtract those calories from meals. This tool estimates both numbers for you.

A small training treat is roughly 2 to 5 kcal. Check the bag, or use a piece of kibble (about 3 kcal) or a pea-sized bit of chicken (about 1 to 2 kcal).

This is an estimate to keep training honest, not veterinary advice. Real calorie needs vary with metabolism, body condition, and health. If your dog is over or under weight, or on a prescription diet, ask your vet for a target, and use a body-condition score rather than the scale alone.