BMI Calculator
BMI
23.1
Normal weight
BMI Calculator: Weight Category and Daily Calories
Enter weight and height in kg and cm to get BMI and a WHO-style category (underweight, normal, overweight, obese). Add age, sex, activity level, and a goal to see BMR and a daily calorie target. Loss goal subtracts 500 kcal from TDEE; muscle gain adds 500 kcal. Screening only, not a medical diagnosis.
How to use
BMI = weight kg ÷ (height m)². Adult WHO bands: under 18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight, 30+ obese. BMR uses Mifflin-St Jeor from sex, age, weight, and height. Daily calories = BMR × activity (1.2 sedentary through 1.9 extra active), then adjust for goal. Desk job plus three gym sessions is often lightly or moderately active, not extra active.
Example
75 kg and 175 cm gives BMI about 24.5 (upper normal). A 30-year-old man at moderate activity might show BMR near 1,700 kcal and maintenance near 2,600 kcal before a loss goal removes 500 kcal.
Tips
BMI cannot tell muscle from fat. Athletes may read overweight while staying lean. Belly fat carries more risk than hip fat, which BMI does not show, so add waist measure and trend. Consider a clinician if BMI is under 18.5 or 30+, or weight shifts quickly without explanation. Pair with the body-fat or TDEE tools on Calctivo for composition and maintenance numbers.