Health & Fitness Calculators
These health and fitness calculators use widely accepted, science-based formulas — Mifflin-St Jeor for calories and BMR, the US Navy method for body fat, standard WHO ranges for BMI. Use them to set a starting point for your goals, then adjust based on real-world results. They are educational tools, not medical advice: for personal health decisions, talk to a qualified professional.
BMI CalculatorBody mass index and healthy weight range in seconds.
Calorie CalculatorDaily calories to maintain, lose or gain weight.
Age CalculatorExact age in years, months and days from your birth date.
Pregnancy Due Date CalculatorEstimated due date and current week of pregnancy.
BMR CalculatorCalories your body burns at complete rest.
Body Fat CalculatorBody fat percentage from tape measurements (US Navy method).
TDEE CalculatorTotal calories you burn per day, at every activity level.
Ideal Weight CalculatorIdeal weight for your height by multiple formulas.
Water Intake CalculatorDaily water target in liters, cups and glasses.
Macro CalculatorDaily protein, carbs and fat targets in grams.
Protein Intake CalculatorDaily protein target in grams, by body weight and goal.
Heart Rate Zone CalculatorYour 5 training zones — fat burn to VO2 max.
Body Surface Area CalculatorBSA in m² — Mosteller and Du Bois formulas.
Lean Body Mass CalculatorFat-free mass via the Boer formula or your body fat %.
Waist-to-Hip Ratio CalculatorWHR with WHO risk categories — what BMI misses.
Calories Burned CalculatorCalories burned by activity, weight and duration.
Steps to Calories CalculatorSteps → distance and calories, from your height & weight.
Ovulation CalculatorOvulation day, fertile window and next period.
Running Pace CalculatorPace per km & mile from distance and time, with splits.
One Rep Max Calculator1RM from any set, plus your %1RM training table.
Smoking Cost CalculatorYour cigarette spend per year — and its invested value.
Blood Pressure CheckerWhere your BP reading falls — normal to hypertensive.