BMI Calculator Metric (kg/cm) 2026 — Free Online

Calculate your Body Mass Index (BMI) instantly using our free online BMI Calculator. BMI is a widely used screening tool that estimates whether you are at a healthy weight relative to your height. Results show your BMI value with healthy weight range, category (underweight / normal / overweight / obese), and actionable health context. Enter your height and weight, and the calculator instantly shows your BMI score, weight category, and healthy weight range. No sign-up required — runs entirely in your browser.

Frequently Asked Questions

How do I calculate BMI using metric units (kg and cm)?

Metric BMI formula: BMI = weight(kg) ÷ height(m)². Example: a person weighing 70 kg at 175 cm has a BMI of 70 ÷ (1.75 × 1.75) = 70 ÷ 3.0625 = 22.9, which falls in the normal healthy range (18.5–24.9). Always convert height from centimetres to metres before calculating.

What are the BMI categories in the metric system?

BMI categories are the same regardless of measurement system: Under 18.5 = Underweight; 18.5–24.9 = Normal weight; 25–29.9 = Overweight; 30–34.9 = Obese Class I; 35–39.9 = Obese Class II; 40+ = Severely obese. These WHO classifications apply globally for adults aged 18 and over.

What is a healthy weight range for my height in metric?

To find your healthy weight range, multiply your height in metres squared by 18.5 (lower) and 24.9 (upper). For 170 cm: healthy weight = 1.70² × 18.5 to 1.70² × 24.9 = 53.5 kg to 71.9 kg. Our metric BMI calculator shows this range instantly after you enter your details.

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