My adopted senior dog is around 25 lbs. We've put her on a diet and am hoping to get her down to 20 lbs. I first bought her a bag of the reg size dry kibbles... but had to dampen it as she has lost most of her teeth. Then I purchased the small kibbles and do not have to dampen it. She really likes it. Depending on your dog's age and if he or she has all her teeth, I would think the regular kibbles would do.