Note: Breed is a starting point. Always adjust for your dog’s individual chew intensity, dental health, and age. Jaw strength (PSI) values are breed averages based on published veterinary bite force research. Senior age thresholds follow veterinary guidelines: Giant breeds (90+ lbs) at 5–7 yrs, Large (50–90 lbs) at 6–8 yrs, Medium (20–50 lbs) at 8–10 yrs, Small/Toy (under 20 lbs) at 10–13 yrs. When in doubt, start softer and move up.