Enter your dog's weight and the chocolate they ate to get an estimated risk level. This calculator is based on published theobromine toxicity thresholds — it is a triage guide, not a substitute for veterinary advice.
Chocolate toxicity in dogs is caused primarily by theobromine, a methylxanthine compound (same class as caffeine) that dogs metabolise far more slowly than humans. In dogs, theobromine's half-life is 17.5 hours — compared to about 3 hours in people. This means it accumulates to toxic levels.
Chocolate also contains caffeine, which contributes to toxicity but at lower concentrations than theobromine. The two compounds have a synergistic effect.
| Chocolate Type | Theobromine (mg/g) | 1 oz contains | Risk Level |
|---|---|---|---|
| White chocolate | 0.44 mg/g | 12 mg | Very Low |
| Milk chocolate | 1.9 mg/g | 54 mg | Low–Moderate |
| Semi-sweet / dark chips | 5.5 mg/g | 156 mg | Moderate |
| Dark chocolate (70%+) | 16 mg/g | 453 mg | High |
| Baking chocolate / cocoa powder | 26 mg/g | 737 mg | Very High |
Source: Gwaltney-Brant S. Chocolate intoxication. Vet Med 2001; 96:108-111. Thresholds are approximate and individual sensitivity varies — small, elderly, or unhealthy dogs may be affected at lower doses.