Dog ate chocolate? Work out the dose, then call your vet
If your dog has eaten chocolate, call your vet or an animal poison helpline first — the numbers are at the top of this page. This chocolate toxicity calculator helps you give them the facts they will ask for: what kind of chocolate, how much, and how heavy your dog is. It turns those into a dose of theobromine and caffeine in milligrams per kilogram of body weight, which is how vets judge the risk.
The content of each chocolate type and the dose levels come from the Merck Veterinary Manual chapter on chocolate toxicosis, written by a veterinarian at the ASPCA Animal Poison Control Center. Dark chocolate with a cocoa percentage on the label is handled too, using Merck’s rule that the percentage reflects the share of unsweetened chocolate.
A low number does not mean your pet is safe. Chocolate differs between brands and batches, owners often underestimate how much was eaten, and some dogs react more strongly. Treat the result as information to pass on, not as a reason to wait.
How to use the Chocolate Toxicity Calculator
- Choose dog or cat and enter your pet’s weight in kg or lb.
- Pick the type of chocolate. For a dark bar with a cocoa % on the wrapper, choose that option and type the percentage.
- Enter the amount eaten in grams or ounces — if unsure, assume the most it could have been.
- Read the dose in mg/kg, the severity band and the table showing how much of this chocolate would reach each level.
- Call your vet or a poison helpline and tell them the type, amount, time eaten and your pet’s weight.
Chocolate Toxicity Calculator features
Vet-reference values
Methylxanthine content per gram and dose bands from the Merck Veterinary Manual (ASPCA Animal Poison Control Center author).
Cocoa % support
A 70% bar contains about 0.70 × 15.5 = 10.9 mg per gram — much more than “dark chocolate” in general.
Severity meter
An animated marker on a scale from 0 to 120 mg/kg, coloured by the published bands.
Threshold amounts
Shows how many grams or ounces of the same chocolate would reach 20, 40, 60 and 100 mg/kg for your pet.
Helplines on the page
US and UK animal poison lines, and what to do elsewhere, always visible above the calculator.
Theobromine and caffeine by chocolate type
Source: Merck Veterinary Manual, “Chocolate Toxicosis in Animals” (full review September 2024, updated February 2026; checked October 2026). Values are methylxanthines — theobromine plus caffeine, with theobromine at three to ten times the caffeine content.
| Chocolate | mg per gram | mg per ounce |
|---|---|---|
| Cocoa powder (dry) | 28.5 | 807 |
| Unsweetened baking chocolate | 15.5 | 440 |
| Cocoa bean hulls / mulch | 9 | 255 |
| Dark chocolate, 70% cocoa (calculated) | 10.9 | 308 |
| Semisweet or sweet dark | 5.3–5.6 | 150–160 |
| Milk chocolate | 2.3 | 64 |
| White chocolate | 0.04 | 1.1 |
Dose bands and a worked example
Example: a 10 kg dog eats a 100 g bar of 70% dark chocolate. 100 g × 10.85 mg/g = 1,085 mg; ÷ 10 kg = 108.5 mg/kg — an emergency. The same dog eating 50 g of milk chocolate gets 115 mg, or 11.5 mg/kg: below the mild-sign level, but still worth a call.
Signs usually start within 6–12 hours and can last up to 72 hours in severe cases, because dogs clear theobromine slowly (half-life about 17.5 hours). Vets may make a dog vomit if the chocolate was eaten recently, typically within about two hours — do not try this at home.
- About 20 mg/kg — mild signs: vomiting, diarrhoea, increased thirst.
- 40–50 mg/kg — heart effects such as a racing or irregular heartbeat.
- 60 mg/kg and above — tremors and seizures.
- 100–200 mg/kg — reported oral lethal dose range, although deaths occur at lower doses.
Chocolate toxicity in cats
Cats are poisoned by the same compounds, but they rarely eat chocolate, and the veterinary reference used here gives dose levels for dogs only. The calculator still shows the mg/kg dose for a cat so you can tell your vet, but it does not claim a safe level. For everyday feeding questions see the cat food calculator.
Chocolate Toxicity Calculator FAQ
How much chocolate is toxic to a dog?
Mild signs are reported from about 20 mg of theobromine and caffeine per kg. For milk chocolate that is roughly 9 g per kg of dog; for 70% dark chocolate under 2 g per kg; for cocoa powder well under 1 g per kg. Use the chocolate toxicity calculator for your dog’s weight.
My dog ate chocolate but seems fine. Should I wait?
No. Signs can take 6–12 hours to appear, and treatment works best early. Call your vet or a poison helpline now and follow their advice.
Is white chocolate safe for dogs?
It contains almost no theobromine, so poisoning is very unlikely, but the fat and sugar can still cause vomiting, diarrhoea or pancreatitis. Wrappers and xylitol-sweetened products are other dangers — tell your vet everything that was eaten.
Why does dark chocolate matter so much?
The darker the chocolate, the more cocoa solids and therefore theobromine it contains. A 70% bar has about five times the theobromine of milk chocolate per gram.
Can I make my dog vomit at home?
Do not, unless a vet tells you exactly how. Home remedies such as salt water can be dangerous. Your vet can do it safely if it is still useful.
Is this a substitute for a vet?
No. Ask your vet — this is general information, not veterinary advice. For a healthy diet afterwards, the dog food calculator helps plan daily amounts.