Dog Chocolate Toxicity Calculator
Enter your dog’s weight, the type of chocolate and how much was eaten. You will get the theobromine dose in mg per kg and what that dose means clinically.
A standard chocolate bar is about 45 g. Guess high if you are unsure.
Most chocolate bars, filled bars and advent calendars.
Minimal risk
10.0 mg theobromine per kg
Below the dose where poisoning signs are normally seen. Rich, fatty food can still cause an upset stomach or, rarely, pancreatitis.
Watch your dog for the next 12 hours. Call your vet if you see vomiting, diarrhoea, restlessness or a racing heart.
- Theobromine eaten
- 200.0 mg
- Caffeine eaten
- 20.0 mg
- Combined methylxanthines
- 11.0 mg/kg
- Amount that would reach the toxic threshold
- 200 g
How this is calculated
Chocolate poisoning in dogs is caused by methylxanthines, mainly theobromine with a smaller contribution from caffeine. Dogs metabolise theobromine far more slowly than people do, which is why an amount that does nothing to a human can be dangerous to a dog.
theobromine (mg) = amount eaten (g) × theobromine per gram
dose (mg/kg) = theobromine (mg) ÷ body weight (kg) The dose per kilogram is what matters, not the total amount. Fifty grams of dark chocolate is a minor incident for a Labrador and a genuine emergency for a Chihuahua.
Theobromine content by type
Figures are milligrams per gram of product. Published veterinary tables usually quote milligrams per ounce, which is about 28 times larger; mixing the two up is the most common way these calculations go wrong.
| Type | Theobromine mg/g | Caffeine mg/g |
|---|---|---|
| White chocolate | 0.009 | 0.001 |
| Milk chocolate | 2 | 0.2 |
| Semisweet or dark chocolate chips | 5.3 | 0.7 |
| Dark chocolate, 60-69% cocoa | 6.5 | 0.8 |
| Dark chocolate, 70-85% cocoa | 8 | 0.8 |
| Unsweetened baking chocolate | 15.6 | 1.9 |
| Cocoa powder, unsweetened | 25.6 | 2.3 |
| Dry cocoa beans or nibs | 21.2 | 1.5 |
| Cocoa bean garden mulch | 9 | 0.3 |
| Instant hot cocoa mix (powder) | 1.4 | 0.2 |
| Chocolate syrup | 0.7 | 0.1 |
Dose thresholds
| Dose (mg/kg) | Severity | Expected signs |
|---|---|---|
| under 20 | Minimal risk | Below the dose where poisoning signs are normally seen. Rich, fatty food can still cause an upset stomach or, rarely, pancreatitis. |
| 20–40 | Mild toxicity likely | Vomiting, diarrhoea, increased thirst, restlessness and bloating. |
| 40–60 | Cardiac effects likely | Raised heart rate, abnormal heart rhythm, hyperactivity, tremors, high blood pressure and heavy panting. |
| 60–100 | Seizure risk | Muscle tremors, seizures, collapse and a dangerously high body temperature. |
| 100+ | Potentially fatal | Doses in the 100-200 mg/kg range have caused deaths from heart rhythm failure and prolonged seizures. |
Sources
- Merck Veterinary Manual, Chocolate Toxicosis in Animals (methylxanthine poisoning).
- ASPCA Animal Poison Control Center, published methylxanthine dose thresholds.
- USDA FoodData Central, theobromine and caffeine content of cocoa products.
What to expect at the vet
If your dog ate the chocolate within the last couple of hours and is not yet showing signs, the vet will usually induce vomiting and give activated charcoal to stop further absorption. Charcoal is often repeated, because theobromine is reabsorbed from the gut rather than cleared in one pass.
At higher doses, treatment is supportive: intravenous fluids to speed elimination, medication to control heart rate and seizures, and monitoring on an ECG. Dogs are frequently kept in for 24 to 72 hours because theobromine has a half-life of around 17.5 hours in dogs.
Take the wrapper with you if you have it. The cocoa percentage and the net weight let the vet calculate the dose precisely rather than working from an estimate.
Common questions
How much chocolate is dangerous for a dog?
Poisoning signs generally start at about 20 mg of theobromine per kilogram of body weight. For milk chocolate that is roughly 10 g per kilogram of dog, so about 200 g for a 20 kg dog. For dark chocolate it is about a quarter of that, and for unsweetened baking chocolate about one eighth.
My dog ate chocolate but seems fine. Should I still call a vet?
Yes, if the calculated dose is 20 mg/kg or higher. Signs typically take 6 to 12 hours to appear, and treatment is far more effective before they do. A dog that looks normal an hour after eating a large amount is not in the clear.
Why is dark chocolate so much worse than milk chocolate?
Theobromine comes from cocoa solids, and dark chocolate contains far more of them. Milk chocolate holds about 2 mg of theobromine per gram, dark chocolate 5 to 8 mg, and unsweetened baking chocolate around 15.6 mg. Cocoa powder, at about 25.6 mg per gram, is the most concentrated form in a normal kitchen.
Is white chocolate safe for dogs?
White chocolate contains almost no theobromine, roughly 0.009 mg per gram, so toxicosis is not the concern. The fat and sugar still can be: a large amount can trigger vomiting, diarrhoea or pancreatitis, particularly in small or predisposed dogs.
Should I make my dog vomit?
Not unless a vet or a poison control line tells you to. Inducing vomiting can be harmful in a dog that is already showing tremors or seizures, or that has eaten something else alongside the chocolate. Phone first.
How long does chocolate toxicity last?
Theobromine clears slowly in dogs, with a half-life of about 17.5 hours, so signs can persist for 24 to 72 hours. Dogs are often hospitalised for monitoring across that window rather than treated and sent home.
What about cocoa mulch in the garden?
Cocoa bean mulch contains theobromine at around 9 mg per gram and smells strongly of chocolate, which is exactly why dogs eat it. It is included as an option in the calculator above.