BMI Calculator

BMI stands for Body Mass Index. It is a numerical value derived from a person’s height and weight. It is used as a general screening tool to classify individuals into weight categories such as underweight, normal weight, overweight, or obese.

• Metric formula: BMI = weight (kg) / height² (m²) • Imperial formula: BMI = (weight (lb) / height² (in²)) × 703

BMI is typically categorized as follows: • Underweight: Less than 18.5 • Normal weight: 18.5 – 24.9 • Overweight: 25 – 29.9 • Obese: 30 and above

BMI provides a quick and non-invasive assessment of whether your weight may be contributing to health risks such as heart disease, diabetes, stroke, or hypertension.

Not always. BMI does not distinguish between fat and lean mass, so athletes with high muscle may be misclassified as overweight, and elderly individuals with low muscle may be considered healthy weight despite high fat levels.

No. For individuals aged 2 to 19, BMI must be interpreted using age- and sex-specific percentile charts because body composition changes with development.

• Doesn’t distinguish fat vs. muscle • Ignores fat distribution • Doesn’t reflect metabolic health • Less reliable for pregnant women, athletes, or the elderly

Yes. Some people with a high BMI may still be metabolically healthy, especially if they have normal blood pressure, cholesterol, and glucose, high fitness levels, and healthy lifestyle habits.

A BMI between 18.5 and 24.9 is generally considered healthy for adults. Your ideal range may vary based on body composition, medical history, ethnicity, and professional guidance.

The BMI formula remains the same, but interpretation may vary: Asians may be at risk at lower BMIs, Black athletes may have higher BMI due to muscle mass, and women typically have higher body fat than men at the same BMI.

Improving BMI involves eating a balanced, nutrient-rich diet, engaging in regular physical activity, managing stress and sleep, and consulting a health professional for personalized guidance.

BMI is helpful for assessing pre-pregnancy health, but it's not used during pregnancy due to natural weight gain and body changes. Healthcare providers use other metrics to monitor pregnancy health.

No. BMI is a height-weight ratio, while body fat percentage measures how much of your body is actual fat. They offer different insights — ideally, both should be considered for a full picture of health.

Yes. Depending on your health goals, other methods may be more accurate, such as: waist circumference, waist-to-hip ratio, body fat analysis (DEXA, BIA, calipers), and metabolic assessments.

You can calculate your BMI using our free online BMI Calculator right here on bmicalconline.com. Just enter your height and weight to get instant results.