Pet Medication Dose by Weight Calculator

About this calculator

This calculator determines a pet's medication dose in two steps: first, total dose (mg) = body weight (kg) × the prescribed dose per kilogram (mg/kg), then that mg figure is converted into a liquid volume (mL) by dividing by the medication's concentration (mg/mL) — and if the drug is given multiple times a day, it multiplies by frequency to show the total daily amount.

Dosing errors are a common and serious risk in home veterinary care because pet medications, unlike most human prescriptions, are frequently dosed by weight with concentrations that vary between brands and formulations. Pet owners administering a prescribed liquid medication and veterinary technicians double-checking a dosage use this calculation to convert a vet's mg/kg instruction into the exact mL to draw up in a syringe — always following the prescribing veterinarian's specific dose and frequency rather than a generic guideline.