Veterinary Fluid Rate Calculator

About this calculator

Veterinary maintenance fluid needs are commonly estimated from body weight using formulas such as 2–4 mL/kg/hour or the resting energy requirement equation 70 × (weight in kg)^0.75 for daily maintenance calories converted to a rough fluid volume, then adjusted for the animal's estimated percent dehydration (deficit in liters = % dehydration × body weight in kg). Adding the maintenance and deficit volumes over a chosen rehydration period gives a total daily fluid target.

This calculator converts that daily target into an hourly infusion rate and a drip rate in drops per minute for a standard giving set (commonly 15 or 20 drops/mL), so it can be dialed in on a gravity drip line without an infusion pump. Veterinary technicians and small-animal clinics use it when setting up maintenance or rehydration fluids for dogs and cats, as a starting reference alongside the treating veterinarian's clinical judgment rather than as a substitute for it.