How the dose is estimated
Theobromine (mg) = Ounces eaten × mg per ounce for the chocolate type
Dose (mg/kg) = Theobromine ÷ Dog weight (kg)
Dose (mg/kg) = Theobromine ÷ Dog weight (kg)
Theobromine contents use the upper values published in the Merck Veterinary Manual: white 0.25, milk 58, semisweet and dark 150, unsweetened baking 450 and dry cocoa powder 737 mg per ounce. Real products vary, and chocolate also contains caffeine, which adds to the effect.
Example: A 30 lb (13.6 kg) dog eats 3 oz of dark chocolate — about 450 mg of theobromine, or 33 mg/kg. That is in the mild-to-moderate toxicity range: call a vet now. The same amount of milk chocolate would be about 13 mg/kg.
Important
- This calculator is an estimate, not a diagnosis. Puppies, older dogs and dogs with heart disease can react to lower doses.
- Wrappers, raisins, nuts and xylitol in sweets can be dangerous on their own.
- Keep the packaging — it helps your vet estimate the dose.
Know your dog’s daily calorie needs with the dog food calculator.
Frequently asked questions
How much chocolate is toxic to a dog?
Mild signs can appear from about 20 mg of theobromine per kg of body weight, heart effects at 40–50 mg/kg and seizures at 60 mg/kg or more. Dark and baking chocolate reach these doses with much smaller amounts than milk chocolate.
Which chocolate is most dangerous?
Cocoa powder and unsweetened baking chocolate contain the most theobromine (up to about 450–740 mg per ounce), then dark and semisweet (about 150 mg/oz), then milk chocolate (about 58 mg/oz). White chocolate has almost none but is high in fat.
What are the signs of chocolate poisoning?
Vomiting, diarrhea, thirst, restlessness, panting, a racing heart, tremors and, in severe cases, seizures. Signs usually start 6–12 hours after eating and can last days.
What should I do if my dog ate chocolate?
Call your veterinarian or a pet poison hotline right away with your dog’s weight, the type and amount of chocolate and when it was eaten. Do not induce vomiting at home unless a vet tells you to.