Health, Fitness & Metabolic Calculators
Optimize your physical wellness and training targets with validated clinical formulas. Compute body mass index, basal metabolic energy expenditure, running marathon splits, and pregnancy gestational age.
Available Health & Fitness Calculators
BMI (Body Mass Index) Calculator
PopularOfficial WHO metric and imperial weight category index
Calorie, TDEE & Macro Deficit Calculator
NewDaily calories for fat loss, muscle gain & macro splits
Running Pace & Marathon Split Calculator
NewCalculate min/mile and min/km splits for 5K to 26.2 marathons
Pregnancy Due Date & Trimester Timeline
PopularEstimated delivery date and gestational development calendar
Sobriety & Recovery Milestone Tracker
Track clean days, health milestones & financial savings
Rehab Cost & Treatment Estimator
Estimate detox, inpatient, and outpatient recovery expenses
Body Fat Percentage Calculator (US Navy Method)
NewCalculate body fat percentage and fat vs lean mass using circumference measurements
Basal Metabolic Rate (BMR) Calculator
NewCalculate resting daily calories burned at complete physical rest
Ideal Body Weight Calculator
NewCompare ideal body weight estimates using Devine, Robinson, and Miller formulas
Lean Body Mass (LBM) Calculator
NewCalculate lean tissue weight and fat mass using Boer and James equations
Ovulation & Fertility Window Calculator
NewCalculate estimated ovulation day, fertile window, and next menstrual cycle
Conception Date Calculator
NewEstimate the exact conception date based on due date, ultrasound, or last period
Menstrual Period & Cycle Tracker
NewPredict your next 3 menstrual periods and PMS symptom phases
Pregnancy Weight Gain Calculator
NewTrack healthy gestational weight gain guidelines by trimester
One Rep Max (1RM) Calculator
NewCalculate 1RM strength and training percentage percentages across Brzycki, Epley, and Lombardi formulas
Target Heart Rate & Training Zones Calculator
NewCalculate aerobic, anaerobic, and VO2 max heart rate zones using the Karvonen method
Blood Alcohol Content (BAC) Calculator
NewCalculate estimated blood alcohol concentration and sober-up timeline using Widmark's formula
Macronutrient Split Calculator
NewCalculate daily protein, carbohydrate, and fat targets for cutting, bulking, or maintaining
Daily Protein Requirement Calculator
NewCalculate optimal protein intake in grams for muscle building, endurance, or fat loss
Daily Water Intake & Hydration Calculator
NewCalculate optimal daily fluid intake based on body weight, climate, and exercise
Body Type & Shape Calculator
NewDetermine body frame shape and Waist-to-Hip Ratio (WHR) health risk
Calories Burned by Activity Calculator
NewCalculate calories burned across 20+ sports using Metabolic Equivalent (MET) scores
Intermittent Fasting Schedule Calculator
NewCalculate eating and fasting windows for 16:8, 18:6, 20:4, and OMAD diets
GFR Kidney Function Calculator (CKD-EPI)
NewCalculate estimated Glomerular Filtration Rate (eGFR) and kidney disease staging
Caffeine Half-Life & Sleep Clearance Calculator
NewCalculate remaining caffeine in your bloodstream and optimal cutoff time for sleep
REM Sleep Cycle & Bedtime Calculator
NewCalculate optimal wake-up times and bedtimes based on 90-minute REM cycles
Mifflin-St Jeor Metabolic Energy Formula
Basal Metabolic Rate (BMR) is calculated via Mifflin-St Jeor: For Men: BMR = (10 × weight_kg) + (6.25 × height_cm) – (5 × age) + 5. For Women: BMR = (10 × weight_kg) + (6.25 × height_cm) – (5 × age) – 161. Total Daily Energy Expenditure (TDEE) multiplies BMR by physical activity level.
Frequently Asked Questions
How accurate is the BMI calculator for athletes and muscular individuals?
BMI is an epidemiological screening tool based on weight and height. It does not differentiate between lean muscle mass and adipose tissue; bodybuilders and strength athletes often rank as "overweight" or "obese" despite having very low body fat percentages.
How many calories should I cut to lose 1 pound of fat per week?
One pound of human adipose tissue represents approximately 3,500 calories. A daily caloric deficit of 500 kcal below your Total Daily Energy Expenditure (TDEE) produces approximately 1 pound (0.45 kg) of fat loss per week.
How is pregnancy due date estimated?
Using Naegele's rule, due date is estimated by adding 280 days (40 weeks) to the first day of your last menstrual period (LMP), assuming a standard 28-day menstrual cycle.