Why chocolate is dangerous — and why the type matters
Chocolate contains methylxanthines — mostly theobromine, plus caffeine — which dogs metabolize very slowly. The darker and less sweet the chocolate, the more concentrated the danger:
| Chocolate type | Methylxanthines (approx.) |
|---|---|
| White chocolate | ~0.1 mg/g — negligible, but fat/sugar can still upset the stomach |
| Milk chocolate | ~2.4 mg/g |
| Dark (45–60%) | ~5.5 mg/g |
| Dark (70–85%) | ~9 mg/g |
| Baking / unsweetened | ~16 mg/g |
| Cocoa powder | ~26 mg/g |
Risk scales with dose per kilogram of dog, which is why the same bar is a very different event for a Chihuahua and a Labrador. In broad veterinary terms: mild signs (vomiting, diarrhea, restlessness) may appear around 20 mg/kg, cardiac effects around 40–60 mg/kg, and seizures above 60 mg/kg. But individual dogs vary, other health issues change the picture, and estimates of "how much they ate" are usually guesses — all reasons the calculator's answer to borderline cases is always the same: call your vet.
What to do, step by step
1. Move the remaining chocolate out of reach (dogs go back for seconds). 2. Work out type and a generous estimate of the amount — wrappers help. 3. Run the numbers above. 4. For anything beyond a clearly trivial dose, or if you're unsure of amount or type, call your vet — they'll weigh the timing, your dog's health and whether inducing vomiting or activated charcoal makes sense. 5. Watch for symptoms for at least 12 hours; they typically start within 6–12 and can last a day or more.
One more villain worth knowing: some chocolate products (and many sugar-free sweets) contain xylitol, which is severely toxic to dogs at tiny doses and acts fast. If the label lists xylitol, that's an immediate vet call regardless of what this calculator says about the chocolate itself.
Frequently asked questions
My 10 kg dog ate 50 g of milk chocolate — is that dangerous?
That's roughly 12 mg/kg — below the level where signs usually appear, so mild stomach upset is the most common outcome. Monitor closely for 12+ hours and call your vet if any symptoms show or if the amount might have been larger than you think.
How long after eating chocolate do symptoms appear?
Usually within 6–12 hours: vomiting, diarrhea, restlessness and thirst first; racing heart, panting and tremors at higher doses. Because theobromine clears slowly, signs can persist a day or more.
Should I make my dog vomit?
Not on your own. Inducing vomiting is sometimes right and sometimes harmful — it depends on timing, dose and your dog's condition. Call your vet first; if it's warranted, they'll do it safely or tell you exactly how.