Dog Chocolate Toxicity Calculator
If your dog has eaten chocolate, call now. Your veterinarian, or the ASPCA Poison Control at (888) 426-4435, open 24 hours. A consultation fee may apply. Use the numbers below to tell them what your dog weighs and what it ate — do not use them to decide whether to call.
Chocolate is toxic to dogs because of its methylxanthines — theobromine and caffeine. How dangerous a given amount is depends on three things: what your dog weighs, which chocolate it was, and how much it ate. Darker chocolate carries far more.
Estimated dose
9.4 mg/kg
for a 30 lb dog that ate 2 oz of milk chocolate.
Below the published threshold
Not sure how much? Check the net weight printed on the package — that is the ounce figure to use. When in doubt, enter the larger amount.
This dose is under 20 mg/kg, the lowest threshold at which the Merck Veterinary Manual describes clinical signs. That is not the same as no risk: dogs differ, and the amount eaten is almost always underestimated. Call your veterinarian or the poison control line — that is the right move even under this threshold.
ASPCA Poison Control: (888) 426-4435
How much chocolate is toxic to a dog?
The Merck Veterinary Manual ties clinical signs to the dose per kilogram of body weight: vomiting, diarrhea and excessive thirst from about 20 mg/kg; cardiotoxic effects from 40–50 mg/kg; seizures at 60 mg/kg and above. The lethal dose for half of exposed dogs is 100–200 mg/kg.
Which chocolate is worst?
Methylxanthine content per ounce, from the same manual: cocoa powder 807 mg, baking chocolate 440 mg, dark and semisweet 150–160 mg, milk chocolate 64 mg, white chocolate 1.1 mg. An ounce of cocoa powder carries more than 12 times what an ounce of milk chocolate does — which is why the type matters as much as the amount.
Two things this cannot know: how much your dog really ate, and how your dog in particular responds. Signs can take 6 to 12 hours to appear, so their absence right now says nothing — call rather than wait for them.
Common questions
What should I do if my dog ate chocolate?
Call your veterinarian, or ASPCA Poison Control at (888) 426-4435, open 24 hours — a consultation fee may apply. Have three things ready: what your dog weighs, which chocolate it was, and roughly how much. The calculator above turns those into a dose in mg/kg, which is the number they will ask for. It is not a number to decide by on your own.
How long before symptoms appear?
The Merck Veterinary Manual describes signs appearing 6 to 12 hours after eating. That delay is a reason to call early rather than to wait and watch: no signs yet tells you nothing about what is already absorbed.
Is white chocolate dangerous too?
White chocolate carries 1.1 mg of methylxanthines per ounce against 807 for cocoa powder, so the dose it delivers is very small. The fat and sugar can still upset a dog’s stomach — run the numbers above and call your veterinarian or the poison control line.
Does the type matter more than the amount?
Both matter, and the type swings the result hardest: an ounce of cocoa powder carries more than 12 times what an ounce of milk chocolate does. A small dog and a dark bar is the combination to worry about most.
This is an estimate of dose, not a diagnosis. Dogs differ, the amount eaten is usually underestimated, and only a veterinarian can decide what a given dog needs. It does not replace professional advice, and it is never a reason to wait.
Verified on . Based on Chocolate Toxicosis in Animals (Merck Veterinary Manual, “Methylxanthine Content of Various Types of Chocolate” table and “Etiology” section, accessed 2026-07-28) and ASPCA Poison Control (ASPCA, 24-hour emergency line, accessed 2026-07-28). See the method.