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Grape & raisin toxicity calculator

There is no known safe amount of grapes, raisins or sultanas for dogs. This tool helps you judge urgency — but you should always phone your vet if your dog ate any.

Count individual grapes or estimate raisins from a handful

Grapes and raisins can cause acute kidney failure — sensitivity varies unpredictably between dogs. This is a guide only and not a substitute for veterinary advice. Read our full grape poisoning guide.

Frequently Asked Questions

Is one grape toxic to dogs?
Some dogs develop kidney failure after a single grape; others appear unaffected. There is no safe dose — always contact your vet if your dog ate any grapes, raisins or sultanas.
Are raisins more toxic than grapes?
Raisins and sultanas are concentrated grapes and are considered at least equally toxic. Foods containing them — mince pies, hot cross buns, cereal — pose the same kidney failure risk.