Health & Fitness

32 calculators: BMI, BMR, TDEE, calorie target, body fat % (US Navy + Army), lean body mass, ideal weight (Robinson / Miller / Devine / Hamwi), healthy weight range, macro splitter, carb / protein / fat intake, body surface area, somatotype, 1RM (Epley / Brzycki / Lombardi), target heart rate, max HR, calories burned by activity, running pace + predictor, VO₂ max, pregnancy due date + weight gain, ovulation, period tracker, sleep cycle, BAC, GFR (kidney function), and steps-to-calories.

BMI is a screening tool, not a diagnosis. It doesn't distinguish muscle from fat. South Asians develop metabolic risk at lower BMIs than Europeans — ICMR recommends 23 (overweight) and 25 (obese) cut-offs instead of WHO's 25 and 30. Pair BMI with Body Fat % and waist-to-height ratio for a fuller picture.

No. CalcMaster's health calculators are educational. For any actionable health concern — weight loss, fertility planning, alcohol-related driving decisions, kidney function — talk to a doctor. We share the math behind the numbers; we don't replace clinical judgment.

We use Mifflin-St Jeor for BMR (the modern standard, more accurate than older Harris-Benedict). TDEE = BMR × activity multiplier (1.2–1.9). Real-world variation is ±10% from genetics and muscle mass. Direct measurement (indirect calorimetry) is more accurate but only available in labs.

BMR = calories burned at complete rest (organs, breathing). TDEE = total daily expenditure = BMR × activity. Eat at TDEE to maintain weight; subtract 500 kcal/day for ~0.5 kg/week loss.

We offer 4 presets (balanced 30/40/30, low-carb 40/20/40, keto 25/5/70, endurance 20/60/20). Bodybuilders need higher protein (2-2.2 g/kg); endurance athletes need higher carbs. Talk to a registered dietitian for personalised macros.

The Pregnancy Due Date and Pregnancy Weight Gain calculators are designed for pregnancy. Other health calculators (BMI, calorie, alcohol BAC) should NOT be used during pregnancy without medical supervision — your metabolism and tolerance differ.