How much chocolate is toxic to dogs?

Toxicity depends on the dog's weight, the type of chocolate, and the amount. Signs typically begin around 20 mg of theobromine per kg of body weight and become serious near 40 mg/kg. Milk chocolate has about 2.3 mg/g, semisweet about 5.6 mg/g, 70–85% dark chocolate about 8.8 mg/g, and baking chocolate about 16 mg/g.

How long until symptoms appear?

Symptoms of chocolate poisoning in dogs usually appear within 6 to 12 hours and can include vomiting, restlessness, rapid heart rate, tremors, and seizures. A dog acting normally soon after eating chocolate is not necessarily safe.

Is white chocolate dangerous to dogs?

White chocolate contains almost no theobromine, so poisoning risk is low, but its high fat and sugar can cause stomach upset or pancreatitis in some dogs.

VeterUSA · Emergency triage

Did your dog eat chocolate?

Enter your dog's weight, the type of chocolate, and roughly how much they ate. You'll get the theobromine dose (mg/kg) and a clear risk level. Dark, semisweet, and baking chocolate are far more dangerous than milk chocolate.

Signs can take 6–12 hours to appear. A normal-acting dog is not a safe dog yet. When in doubt, get advice before symptoms start — it's cheaper and safer than waiting.

Your dog's weight A rough number is fine.

Type of chocolate If unsure, pick the darkest it could be — that's the safer assumption.

Amount eaten (grams) Estimate is fine. Weigh the wrapper if you still have it.

Rough reference

Standard milk chocolate bar~43 g
Square of baking chocolate~28 g
Handful of chocolate chips~40 g
1 tbsp cocoa powder~5 g

How chocolate poisons dogs

Chocolate contains theobromine and caffeine — stimulants dogs metabolize far more slowly than humans. Theobromine is the main problem. It builds up and overstimulates the heart and nervous system. The darker and more bitter the chocolate, the more theobromine per gram, which is why a few squares of baking chocolate is a bigger emergency than a whole milk-chocolate bar.

Roughly how much theobromine, by type

Milk chocolate ~2.3 mg/g · semisweet/dark under 60% ~5.6 mg/g · dark 60–85% cacao up to ~8.8 mg/g · baking/unsweetened ~16 mg/g · cocoa powder ~28.5 mg/g · white chocolate is negligible. These figures are theobromine plus caffeine, which act together. Signs generally start around 20 mg/kg of body weight, become serious near 40 mg/kg, and are potentially life-threatening above 60 mg/kg.

Symptoms to watch for (6–12 hours)

Vomiting, diarrhea, restlessness or hyperactivity, excessive thirst, panting, a racing or irregular heartbeat, muscle tremors, and in severe cases seizures. Because onset is delayed, a calm dog right now does not mean you're in the clear.

White chocolate note

White chocolate has almost no theobromine, so poisoning risk is low — but it's high in fat and sugar and can trigger pancreatitis, especially in small or predisposed dogs. Watch for repeated vomiting and abdominal pain.

What a vet will do

If it's recent, they may induce vomiting and give activated charcoal to block absorption. Beyond that, care is supportive: IV fluids, heart-rate monitoring, and medication to control agitation or arrhythmias. Caught early, most dogs recover fully.

Educational information, not a diagnosis. This tool estimates a dose from the high end of published theobromine + caffeine values (Merck Veterinary Manual; USDA for 60%+ dark); real chocolate varies. When unsure, always contact a vet or a poison line.

Pet Poison Helpline: (855) 764-7661 · ASPCA Animal Poison Control: (888) 426-4435 (a fee may apply).