Pet Calculators
22 free pet calculators for dog age, cat food, aquarium sizing, chocolate toxicity, and more. No signup required.
22 free tools
Dog Age Calculator
Convert your dog's age to human years by breed size. Adjusts for rapid puppy growth and size-based aging rates.
Dog Food Calculator
Calculate daily food portions for your dog based on weight, age, and activity level using the veterinary RER formula.
Cat Age Calculator
Convert your cat's age to human years. Year 1 = 15, year 2 = 24, then 4 human years per cat year after that.
Cat Food Calculator
Calculate daily calorie needs and food amounts for your cat in wet food oz and dry food cups.
Chocolate Toxicity Calculator for Dogs
Estimate chocolate toxicity risk for your dog by weight, chocolate type, and amount consumed. Shows severity level and action to take.
Aquarium Calculator
Calculate tank volume in gallons and liters for rectangular, cylindrical, and bow-front tanks. Includes fish stocking, heater, and filter recommendations.
Dog Calorie Calculator
Calculate precise daily calorie needs for your dog using the veterinary RER formula and DER life stage factor.
Pet Medication Dosage Calculator
Calculate common OTC medication doses for dogs by weight. Covers Benadryl, Pepto-Bismol, hydrogen peroxide, aspirin, and melatonin.
Fish Tank Water Change Calculator
Calculate water change volume, dechlorinator dose, and aquarium salt amount for your fish tank.
Pet Body Condition Score (BCS)
Assess your dog or cat's body condition on the 1-9 veterinary BCS scale using observable characteristics. Get score, category, and feeding recommendations.
Rabbit Food Calculator
Calculate daily hay, pellet, vegetable, treat, and water amounts for your rabbit based on weight and life stage.
Bird Cage Size Guide
Bird species to minimum cage dimensions and bar spacing.
Pet Cost Calculator
Estimate annual cost of pet ownership by animal type.
Dog Pregnancy Calculator
Due date and timeline from breeding date.
Cat Pregnancy Calculator
Due date from breeding date (63-day gestation).
Dog BMI Calculator
Body condition score from weight and breed size.
Fish Compatibility Guide
Check which freshwater fish species can coexist.
Pond Volume Calculator
Pond dimensions to gallons for pumps and fish stocking.
Guinea Pig Pregnancy Calculator
Due date from breeding date.
Hamster Age Calculator
Hamster-to-human age conversion.
Bird Age Calculator
Bird-to-human age conversion by species.
Cat Calorie Calculator
Daily caloric needs for cats by weight, age, and activity.
About Our Pet Calculators
Every pet calculator on this page is completely free, requires no signup, and runs entirely in your browser. We cover feeding amounts, age conversions, aquarium planning, pregnancy timelines, and health assessments for dogs, cats, birds, fish, rabbits, and small animals.
Whether you are figuring out how much to feed your puppy, checking if the chocolate your dog ate is dangerous, or planning a new aquarium, these tools give you accurate answers instantly. All calculations update live as you type.