BMR and TDEE calculator
Calculate BMR (basal metabolic rate) and TDEE (total daily energy expenditure) using the Mifflin-St Jeor formula. Free calculator.
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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).
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