Tip: a standard milk chocolate bar is about 1.5 oz (43 g). When unsure, estimate high.
This is an estimate only, not a diagnosis. When in doubt, always call your vet or a pet poison helpline.
Talk to a vet now — from home
An online vet can tell you in minutes whether this is an emergency. Pet insurance can also cover poisoning visits, which often cost hundreds.
How chocolate poisoning works in dogs
Chocolate contains theobromine (and some caffeine), stimulants that dogs break down much more slowly than people. The danger depends on three things: how much was eaten, what type of chocolate, and how big your dog is. Darker, more bitter chocolate has far more theobromine than milk chocolate.
As a rough guide used by veterinarians, problems are measured in milligrams of theobromine per kilogram of body weight:
- Under 20 mg/kg — mild or no signs likely, but still worth a call.
- 20–40 mg/kg — stomach upset, restlessness and a racing heart can appear.
- 40–60 mg/kg — heart-rhythm problems become a real risk; call your vet now.
- Over 60 mg/kg — tremors and seizures are possible; treat as an emergency.
Because chocolate recipes vary and every dog is different, this calculator gives a cautious estimate, not a verdict. Puppies, seniors and dogs with heart conditions are more vulnerable. When you're unsure of the amount, assume the worst and call.
What to do if your dog ate chocolate
- Call your vet or a pet poison helpline right away — don't wait for symptoms.
- Note how much and what type was eaten, and when.
- Do not induce vomiting unless a professional tells you to.
- Watch for vomiting, restlessness, a racing heart, tremors or seizures.
For the full guide, see Can dogs eat chocolate?