Pet Toxicity Calculator (Chocolate, Xylitol, Grapes & More)
A triage tool for common pet toxins. Enter what the pet ate, how much, and their weight to get a dose-per-kg comparison against published toxic thresholds. This does not replace a call to your vet - any ingestion warrants professional advice, especially if recent.
Emergency? Call your veterinarian or a poison helpline.
ASPCA Animal Poison Control: (888) 426-4435 (US, fee applies). Pet Poison Helpline: (855) 764-7661 (US/Canada). This tool is a triage aid, not a substitute for veterinary advice.
Substance ingested
Species
Patient weight (kg)
Amount eaten (g)
Thresholds assume DARK chocolate. Multiply g eaten by 7 for milk chocolate, by 100 for white chocolate to get the equivalent toxic dose. Baker's chocolate is even more concentrated than dark.
How to use this tool
Why dose per kg matters more than total amount
A 50 g chocolate bar is fatal to a Chihuahua but barely registers in a Great Dane. Every toxin threshold is per kg of body weight, which is why this tool always asks for weight and the amount eaten separately.
Decontamination is time-critical
Emesis (vomiting up the toxin) is effective in the first 1-2 hours post-ingestion for most ingestible toxins. After that, activated charcoal can still bind some compounds. Beyond 4-6 hours, decontamination is much less useful and supportive care takes over. Don\'t wait and watch - call.
What to tell the vet on the phone
(1) Patient weight, age, species. (2) Substance name and concentration if known (e.g. "dark chocolate, 70% cacao" or "ibuprofen 200 mg tablets"). (3) Estimated amount eaten and time elapsed. (4) Any signs the patient is showing now. (5) Bring the packaging with you - it helps.
Pet poison helplines
ASPCA Animal Poison Control (US): (888) 426-4435 - 24/7, fee applies.
Pet Poison Helpline (US/Canada): (855) 764-7661 - 24/7, fee applies.
UK: Animal PoisonLine 01202 509000.
Australia: Contact your nearest emergency vet directly.
Frequently asked questions
How much chocolate is toxic to a dog?
Roughly 20 mg/kg of theobromine for mild signs, 40-60 mg/kg for moderate-severe, > 100 mg/kg can be lethal. Dark chocolate has ~16 mg theobromine per g; milk chocolate ~2 mg/g; white chocolate negligible. A 10 kg dog and 25 g of dark chocolate = ~40 mg/kg = moderate risk.
Is xylitol toxic to cats?
Xylitol toxicity is primarily a dog problem - cats don't respond to it the same way. In dogs, 0.1 g/kg causes hypoglycaemia; 0.5 g/kg causes hepatic necrosis. Sources include sugar-free gum (0.3-1 g xylitol per piece), sugar-free peanut butter, and some toothpastes.
How many grapes are toxic to a dog?
Any amount can be toxic - sensitivity is highly variable and unpredictable. Reported toxic ranges start at 10-30 g/kg of grapes. Treat all grape and raisin ingestions as potentially toxic and call your vet immediately.
Is the calculator a substitute for calling the vet?
No. Always call your vet or pet poison control for ingestions. The calculator is triage - decontamination is most effective in the first 1-2 hours, and delaying for a self-diagnosis costs that window.