Quick answer: Free biology calculators for pet nutrition, daily energy needs and body composition. Practical tools backed by standard formulas.
All Biology Calculators (7)
Cat Food Calculator: Daily Feeding Guide →Use this free cat food calculator to find your cat's daily feeding amount in cups, from body weight and life stage using the veterinary RER formula.Biology
Dog Food Calculator: Daily Feeding Guide →Use this free dog food calculator to find your dog's daily feeding amount in cups from weight and activity, using the veterinary RER formula.Biology
TDEE Calculator: Daily Calorie Needs →Free TDEE calculator: estimate your total daily energy expenditure with Mifflin-St Jeor, plus weight-loss and muscle-gain calorie targets.BiologyBody Fat Percentage Calculator →Free body fat percentage calculator: US Navy tape-measure method from waist, neck, hip and height, plus a BMI-based estimate and fitness categories.BiologyBMR Calculator - Basal Metabolic Rate →Free BMR calculator: estimate basal metabolic rate with the Mifflin-St Jeor equation and see daily calorie needs for five activity levels.BiologyDog Age Calculator: Human Years & Formula →Free dog age calculator: see your dog's age in human years with the traditional method and the 2019 UCSD epigenetic formula, shown side by side.BiologyHorse Weight Calculator: Tape Method →Free horse weight calculator: estimate weight with the heart-girth tape method for adults, yearlings, weanlings and ponies, in kg or lb. Instant.Biology
Frequently asked questions
Are these biology calculators free?
Yes, every calculator on this page is free with no sign-up.
What can I calculate here?
Daily dog and cat food portions by weight and life stage, total daily energy expenditure (TDEE), basal metabolic rate (BMR), and body fat percentage for humans.
How accurate are the pet food calculators?
They use standard RER/MER veterinary formulas. Always confirm portions with your vet for your specific pet.
Do these work on mobile?
Yes, all calculators work on any device with a modern browser.