BMR and TDEE calculator
Calculate BMR (basal metabolic rate) and TDEE (total daily energy expenditure) using the Mifflin-St Jeor formula. Free calculator.
Health calculators
Current for 2026How we verify data: Methodology →
BMI calculator
Enter your weight and height — the calculator returns your BMI and the WHO category.
Na tej stronie
How we calculate BMI
BMI = weight (kg) / height² (m). WHO categories: underweight < 18.5; normal 18.5–24.9; overweight 25–29.9; obese I° 30–34.9; II° 35–39.9; III° ≥ 40.
Example: 70 kg, 175 cm
For 70 kg and 175 cm: BMI = 70 / 1.75² = 22.86 — normal (18.5–24.9). At 85 kg with the same height BMI = 27.76 — overweight.
Frequently asked questions
How do I calculate BMI?
BMI = weight (kg) / height² (m). E.g. 70 kg, 175 cm → 70 / 1.75² = 22.86.
What is a healthy BMI?
A BMI of 18.5–24.9 is considered normal by WHO.
Is BMI accurate?
BMI is a screening tool; it does not account for body composition. Highly muscular people may have a high BMI without excess fat.
What BMI means obesity?
BMI ≥ 30 is Class I obesity, ≥ 35 Class II, ≥ 40 Class III (morbid obesity).
Is BMI the same for men and women?
The formula is the same, but women naturally have a higher body-fat percentage at the same BMI.
When should I see a doctor?
Consult a doctor if BMI < 17 or ≥ 35. The calculator result is not medical advice.
How do I lower my BMI?
A combination of caloric deficit and physical activity. A safe rate is 0.5–1 kg per week.
What about BMI for children?
Children use age- and sex-adjusted growth charts — not the same thresholds as adults.
Height in cm or m?
Enter height in centimetres — the calculator converts it to metres automatically.
Is the result binding?
No — it is indicative and does not replace medical or dietetic advice.
The result is indicative and does not replace medical advice. BMI does not account for body composition (muscle mass, bone density). This calculator is intended for adults — do NOT use it during pregnancy (consult your midwife/doctor instead) or for children (use the Child BMI Calculator with age/sex growth charts).
Related calculators
New New Calorie and Macronutrient Calculator
Calculate calories from macronutrients: protein, fat, carbohydrates. Free online kcal calculator.
Health calculators
More calculators in Health calculators
Related articles
- How to Calculate BMI and Interpret the Result CorrectlyBMI is a simple body mass index. We explain the formula, WHO ranges and show a step-by-step calculation with an example. Check the interpretation.
- BMI for children — percentile charts and normsWhy a child’s BMI is read from percentile charts rather than fixed thresholds. We explain percentiles, age norms and show an interpretation example.
- Body fat — how to calculate the percentageMethods for measuring body fat: calipers, BIA and the Deurenberg formula from BMI. We explain the percentage norms and show a worked example.
BMI result22.86BMI