Biology Calculators
Health, fitness, and life science calculators
Explore practical tools for body measurements, nutrition, fitness, hydration, sleep, and reproductive health. Each calculator explains its inputs and should be used as an educational estimate—not a medical diagnosis.
BMI Calculator
Calculate body mass index from height and weight.
Open calculator →Daily Calorie Needs
Estimate daily calories using body measurements and activity.
Open calculator →Ideal Weight Calculator
Estimate an ideal body-weight range based on height.
Open calculator →Body Fat Percentage
Estimate body-fat percentage using common measurements.
Open calculator →Maximum Heart Rate
Estimate maximum heart rate and training zones.
Open calculator →Daily Water Intake
Estimate daily hydration needs based on body weight.
Open calculator →Pregnancy Due Date
Estimate a due date from the last menstrual period.
Open calculator →Blood Alcohol Estimate
Estimate blood alcohol concentration from supplied inputs.
Open calculator →Sleep Cycle Calculator
Find suggested wake times using 90-minute sleep cycles.
Open calculator →Protein Intake
Estimate daily protein needs by weight and activity.
Open calculator →TDEE Calculator
Estimate total daily energy expenditure.
Open calculator →Ovulation Calculator
Estimate fertile days from cycle information.
Open calculator →Can’t find the right formula?
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