BMI Calculator

성별

남성여성

나이

30대

Height (cm):

Weight (kg):

What is BMI (Body Mass Index)?

Body Mass Index (BMI) is a simple index of weight-for-height that is commonly used to classify underweight, overweight, and obesity in adults. It allows you to estimate your body fat levels using only your height and weight, without the need for complex equipment. BMI is widely used by healthcare professionals globally as a preliminary screening tool.

💡 Formula: BMI = Weight (kg) ÷ {Height (m) × Height (m)}

Understanding Your BMI Result

While BMI is a useful indicator, standards may vary slightly by region (e.g., WHO vs. Asia-Pacific guidelines). Generally, the ranges are interpreted as follows:

Underweight (Below 18.5): You may need to gain weight through a balanced diet and strength training.
Normal Weight (18.5 – 22.9): You are in a healthy range. Maintain your current lifestyle!
Overweight (23 – 24.9): This is a warning sign ("Pre-obese"). It's a good time to start managing your weight.
Obese (25 and above): Increased risk of health issues such as heart disease and diabetes. Weight loss is recommended.

Tips for Maintaining a Healthy Weight

1. Eat a Balanced Diet

Avoid extreme diets. Instead, focus on regular meals rich in protein, fiber, and essential nutrients.

2. Stay Active

Aim for at least 30 minutes of moderate aerobic exercise, such as brisk walking or jogging, 3 to 5 times a week.

3. Hydration and Sleep

Drinking plenty of water and getting 7+ hours of quality sleep helps regulate your metabolism and prevents overeating.

Frequently Asked Questions

Q. How is BMI calculated?

BMI = weight(kg) ÷ height(m)². For example, 170 cm and 65 kg gives 65 ÷ (1.7 × 1.7) ≈ 22.5, which sits in the normal range. The calculator computes it instantly and shows the matching category.

Q. Are the cutoffs different for Korean / Asian populations?

Yes. The WHO standard treats 18.5-24.9 as normal, but the Korean Society for the Study of Obesity uses stricter thresholds — overweight from 23, obese from 25 — based on Asian-specific risk profiles. The calculator shows both.

Q. If my BMI is normal, am I definitely healthy?

BMI only considers weight and height, so it cannot separate muscle from fat. Muscular athletes can score high while still being fit, and people in the normal range can still carry harmful visceral fat. Pair BMI with a body-composition measurement for the full picture.

Q. What do underweight / overweight / obese classes mean for my health?

Underweight (BMI < 18.5) raises malnutrition risk, overweight (BMI 23-24.9) is a pre-obesity warning, and class I obesity (25-29.9) starts a statistically meaningful rise in hypertension, diabetes, and cardiovascular risk. The calculator shows stage-specific tips.

Q. Does it show my healthy weight range?

Yes. Based on your height, the calculator displays the weight range that falls inside the normal BMI band (18.5-24.9). For 170 cm that's roughly 53.5-72 kg.

Q. Does this apply to children or pregnant people?

No. Children and teens use age- and sex-specific BMI percentiles, and pregnancy uses week-based recommended weight. The calculator targets adults 18+; other groups should consult a clinician.

* This calculator is intended for informational purposes only.
It is not a substitute for professional medical advice, diagnosis, or treatment.

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