All pet calculator tools
Every calculator here runs in your browser, works in pounds or kilograms, cites its formula, and needs no account. Example: a 20 kg neutered adult often needs about 1,075 kcal/day. Choose a tool below, or start from the dog hub or the cat hub.
Puppy Weight Calculator
Predict adult weight from age in weeks, current weight and breed or size. Growth chart in lb and kg; free, private.
Dog Food Calculator
Daily calories and cups from weight, life stage and label kcal per cup. RER/MER factors; lb or kg; free.
Puppy Food Calculator
Calculate puppy feeding amounts by current weight and expected adult size using RER and growth multipliers.
Homemade & Raw Dog Food Calculator
Estimate daily homemade or raw ration portions from body weight. Educational only — balance recipes with a vet nutritionist.
Dog Age Calculator
Dog years to human years by size with AAHA-style life stages and an optional log curve — not the 7:1 myth.
Cat Age Calculator
Estimate your cat’s age in human years with life-stage stages used by veterinary associations.
Cat Food Calculator
Estimate daily kcal and feeding amounts for cats by weight, life stage, and body condition goals.
Dog BMI & Body Condition Helper
Screen body condition with a BMI-style index and the 1–9 BCS scale. Educational helper, not a diagnosis.
Dog Pregnancy & Due Date Calculator
Estimate whelping due date from breeding or ovulation date. Typical gestation is about 63 days.
Dog Chocolate Toxicity Calculator
Estimate theobromine dose from chocolate type, amount and weight. Call a vet or poison hotline if your dog ate chocolate.
Dog Water Intake Calculator
Estimate typical daily water needs from body weight and activity. Sudden changes warrant a vet visit.
Which calculator should I use?
Match the tool to the question you are trying to answer. If you are deciding how much to feed, start with the dog food calculator for adults, the puppy food calculator for growing dogs, or the cat food calculator for cats. They all start from resting energy requirement and a life-stage multiplier, then turn calories into cups using the number on your food label.
If you want to know how big a puppy will get, use the puppy weight calculator. To judge whether a dog is at a healthy size, use the body condition helper alongside a hands-on check of the ribs and waist. For age questions, the dog age calculator and cat age calculator convert calendar years into life stages that are useful for planning vet visits.
Safety and special situations
The chocolate toxicity calculator is a triage aid for the moment after a dog eats something it should not, and it never replaces a call to your vet or a poison hotline. The dog pregnancy calculator estimates a whelping window, and the water intake calculator gives a baseline for normal drinking. If you cook or feed raw, the homemade dog food calculator sizes portions, but a balanced recipe needs a veterinary nutritionist.
How the calculators work
Every result is calculated in your browser using formulas documented on our methodology page. Each tool page repeats its equation, shows a worked example, lists common mistakes, and cites sources such as the National Research Council, WSAVA, AAHA, AAFP, AAFCO, ASPCA, and the MSD Veterinary Manual. Results are estimates for healthy animals and are not veterinary advice.