Health Stats Suite — BMI, TDEE & Ideal Weight Calculator

Height

Weight

Age

yrs

Biological sex

Activity level

Your results

—

UnderweightNormalOverweightObese

BMR — calories at rest

— kcal/day

TDEE — daily needs

— kcal/day

Ideal weight range (BMI 18.5–24.9)

— kg

Calorie goals

Weight loss (−500 kcal/day)	—
Maintenance	—
Mild weight gain (+250 kcal/day)	—

About the Health Stats Suite

The Health Stats Suite combines four research-backed calculations in one form. Enter your height, weight, age, sex and activity level once — the tool instantly computes your BMI, Basal Metabolic Rate, Total Daily Energy Expenditure and ideal weight range.

BMI (Body Mass Index)

Calculated as weight (kg) ÷ height (m)². WHO categories: Underweight <18.5, Normal 18.5–24.9, Overweight 25–29.9, Obese ≥30. BMI is a useful screening indicator but doesn't directly measure body fat — muscular individuals may score higher than expected.

BMR & TDEE

BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest. This calculator uses the Mifflin-St Jeor equation, the most accurate formula for most adults. TDEE multiplies your BMR by an activity factor to give your true daily calorie requirement.

Ideal weight

Expressed as the weight range that would put you in the "Normal" BMI band (18.5–24.9) at your current height. This is a statistical reference point, not a personal prescription.

Using a suite of health metrics together

No single metric tells the complete health story. BMI may flag a muscular athlete as overweight while missing a thin person with high visceral fat. Waist circumference adds a cardiovascular risk dimension. Body fat percentage reveals composition. Resting heart rate reflects cardiovascular fitness. Using all these metrics together gives a much more complete picture than any single measurement.

BMI — quick population-level screening tool; poor for individuals with high muscle mass
Waist circumference — waist above 102cm (men) or 88cm (women) indicates elevated cardiovascular risk
Body fat % — most direct measure of adiposity but requires DEXA or skinfold calipers for precision
BMR — determines minimum calorie intake; essential for accurate weight management planning

Frequently Asked Questions

What BMI formula does this use?

BMI = weight (kg) ÷ height (m)². WHO categories: Underweight <18.5, Normal 18.5–24.9, Overweight 25–29.9, Obese ≥30.

What TDEE formula is used?

The Mifflin-St Jeor equation for BMR, multiplied by an activity factor. Male BMR = 10×weight(kg) + 6.25×height(cm) − 5×age + 5. Female BMR = 10×weight + 6.25×height − 5×age − 161.

Is this a substitute for medical advice?

No. These are estimates based on population averages. Individual metabolism varies. Consult a healthcare professional before making significant dietary or exercise changes.

How accurate are these health metrics?

The Mifflin-St Jeor and WHO formulas are widely validated research-based equations, but all are population-level estimates. They are best used as guidelines rather than precise measurements.

How often should I track my health stats?

For most people, monthly measurements are sufficient for long-term tracking. Daily weight measurements show normal fluctuations (1-3 kg) driven by hydration, digestion, and hormones — tracking the weekly average is more informative than daily readings. Blood pressure should be measured at the same time of day after resting for 5 minutes.

What is a healthy waist circumference?

The NHS recommends a waist circumference below 94 cm (37 inches) for men and 80 cm (31.5 inches) for women to reduce risk of health problems. Above 102 cm for men or 88 cm for women is associated with substantially increased cardiovascular and metabolic risk. Waist circumference is a stronger predictor of metabolic health than BMI alone.