Health & Fitness Calculators
Use health and fitness calculators for body measurements, nutrition, activity, pregnancy timing, heart rate, sleep, and training plans. Results are estimates built from the inputs and equations shown on each page. They support informed planning but do not replace diagnosis, treatment, or advice from a qualified healthcare professional.
What can you calculate here?
Choose a focused tool below for a transparent, shareable result backed by the method and sources shown on its page.
BMI Calculator
Work out your body mass index from height and weight in either units, see which NHLBI category it falls in, and the healthy weight range for your height.
Calorie Calculator
Work out the calories you need each day from the Mifflin-St Jeor equation and FAO activity levels, with targets for losing or gaining weight at a chosen rate.
Body Fat Calculator
Body Fat Calculator derives body fat % from sex, waist measurement, neck measurement, and height.
TDEE Calculator
TDEE Calculator estimates daily energy expenditure from BMR and an entered activity factor.
Macro Calculator
Macro Calculator derives carbohydrate grams from calories, protein percentage, and fat percentage.
Pregnancy Calculator
Pregnancy Calculator estimates a due date from the last menstrual period and cycle length.
BMR Calculator
BMR Calculator estimates resting energy needs from sex, weight, height, and age.
Ideal Weight Calculator
Ideal Weight Calculator estimates Devine weight from sex and entered height measurements.
Healthy Weight Calculator
Healthy Weight Calculator returns a BMI-based weight range from an entered height.
Lean Body Mass Calculator
Lean Body Mass Calculator returns lean mass from weight and entered body-fat percentage.
Due Date Calculator
Due Date Calculator estimates a pregnancy due date from last menstrual period and cycle length.
Ovulation Calculator
Ovulation Calculator estimates an ovulation date from period start and typical cycle length.
Conception Calculator
Conception Calculator estimates a conception date from an entered pregnancy due date.
Period Calculator
Period Calculator computes next period day from last period day and cycle days.
Protein Calculator
Protein Calculator returns daily protein grams from body weight and selected grams-per-kilogram factor.
Carbohydrate Calculator
Carbohydrate Calculator returns daily carbohydrate grams from calorie intake and selected carbohydrate percentage.
Fat Intake Calculator
Fat Intake Calculator returns daily fat grams from calorie intake and selected fat percentage.
Water Intake Calculator
Water Intake Calculator determines water milliliters from weight and ml per kg.
Calories Burned Calculator
Calories Burned Calculator estimates energy used from body weight, exercise duration, and activity intensity.
One-Rep Max Calculator
One-Rep Max Calculator estimates maximum lift from entered weight and completed repetitions.
Target Heart Rate Calculator
Target Heart Rate Calculator returns target HR from age, resting heart rate, and intensity.
Pace Calculator
Pace Calculator returns minutes per distance unit from route length and elapsed time.
BAC Calculator
BAC Calculator estimates blood alcohol concentration from alcohol, weight, sex, and elapsed hours.
GFR Calculator
GFR Calculator computes an estimated filtration rate from creatinine, age, and sex.
Sleep Calculator
Sleep Calculator suggests a bedtime from wake time and desired sleep duration.
Body Surface Area Calculator
Body Surface Area Calculator estimates BSA from entered height and weight using Mosteller’s formula.
Army Body Fat Calculator
Army Body Fat Calculator estimates an Army body-fat percentage from sex, waist measurement, neck measurement, and height.
Body Type Calculator
Body Type Calculator returns a BMI-based body-size result from height and weight.
Pregnancy Weight Gain Calculator
Pregnancy Weight Gain Calculator estimates guideline gain from pre-pregnancy BMI and elapsed weeks.
Overweight Calculator
Overweight Calculator returns a BMI category from entered height and weight measurements.
Sleep Cycle Calculator
Sleep Cycle Calculator suggests bedtime from wake time and complete 90-minute cycles.
Running VDOT Calculator
Running VDOT Calculator returns a training pace estimate from race distance and elapsed minutes.
Macro Cycling Calculator
Macro Cycling Calculator returns a cycling-day calorie target from baseline calories and increase percentage.