Calculate your body mass index (BMI) online. Determine whether your weight meets WHO standards. Fast, accurate and free.
| Category | BMI index (kg/m²) | Interpretation |
|---|---|---|
| Lack of mass | < 18.5 | Weight gain recommended |
| Norm | 18.5 – 24.9 | Healthy body weight |
| Overweight | 25.0 – 29.9 | Possible risk of disease |
| Obesity I degree | 30.0 – 34.9 | Increased risk |
| Obesity II degree | 35.0 – 39.9 | High risk |
| Obesity III degree | ≥ 40.0 | Very high risk |
Body mass index (BMI) is a measure that helps measure whether a person's weight matches their height. Our calculator uses the standard WHO formula to accurately calculate BMI and determine your weight category.
BMI is an important tool for assessing the health risks associated with being overweight or underweight. Although BMI does not take into account muscle mass and other individual characteristics, it remains a widely used indicator in medicine and healthcare.
Let's look at practical examples of calculating body mass index for different cases:
Male, height 175 cm, weight 70 kg
Входные данные:
Weight: 70 kg
Height: 175 cm (1.75 m)Расчёт:
BMI = 70 / (1.75)²
BMI = 70 / 3.0625
BMI = 22.86Результат:
BMI = 22.86
Категория:
Normal weight (18.5-24.9)
Woman, height 165 cm, weight 48 kg
Входные данные:
Weight: 48 kg
Height: 165 cm (1.65 m)Расчёт:
BMI = 48 / (1.65)²
BMI = 48 / 2.7225
BMI = 17.63Результат:
BMI = 17.63
Категория:
Underweight (<18.5)
Male, height 180 cm, weight 90 kg
Входные данные:
Weight: 90 kg
Height: 180 cm (1.80 m)Расчёт:
BMI = 90 / (1.80)²
BMI = 90 / 3.24
BMI = 27.78Результат:
BMI = 27.78
Категория:
Overweight (25-29.9)
Woman, height 160 cm, weight 85 kg
Входные данные:
Weight: 85 kg
Height: 160 cm (1.60 m)Расчёт:
BMI = 85 / (1.60)²
BMI = 85 / 2.56
BMI = 33.20Результат:
BMI = 33.20
Категория:
Obesity I degree (30-34.9)
Male, height 170 cm, weight 110 kg
Входные данные:
Weight: 110 kg
Height: 170 cm (1.70 m)Расчёт:
BMI = 110 / (1.70)²
BMI = 110 / 2.89
BMI = 38.06Результат:
BMI = 38.06
Категория:
Obesity II degree (35-39.9)
Woman, height 155 cm, weight 95 kg
Входные данные:
Weight: 95 kg
Height: 155 cm (1.55 m)Расчёт:
BMI = 95 / (1.55)²
BMI = 95 / 2.4025
BMI = 39.54Результат:
BMI = 39.54
Категория:
Obesity III degree (≥40)
BMI is calculated using the formula recommended by the World Health Organization:
BMI = вес (кг) / (рост (м))²The World Health Organization has defined the following BMI categories:
Optimal weight for health and longevity
Increased risk of developing diseases
Significantly increased health risk
Possible health problems
Our BMI calculator provides many benefits:
To get accurate results, follow these guidelines:
BMI has some limitations and does not take into account:
BMI (Body Mass Index) is a body mass index that shows the ratio of weight to height. It is used to assess the risk of diseases associated with being overweight or underweight. Calculation formula: BMI = weight (kg) / (height (m))².
To calculate BMI online, enter your weight in kilograms and height in centimeters into the calculator. The system will automatically calculate your body mass index using the WHO formula and show your weight category: normal, underweight, overweight or obese.
The normal BMI for women is 18.5-24.9 kg/m². This range corresponds to the lowest health risks. Values below 18.5 indicate underweight, and values above 25 indicate overweight or obesity.
Normal BMI for men is also 18.5-24.9 kg/m². This range is optimal for health regardless of gender. A BMI above 25 indicates overweight, and above 30 indicates obesity.
Underweight is defined as a BMI below 18.5 kg/m². This may indicate malnutrition, health problems or constitutional issues. It is recommended to consult a doctor to assess your health status.
Overweight is defined as a BMI of 25-29.9 kg/m². This indicates being above the normal weight range and may increase the risk of cardiovascular disease. It is recommended to review your diet and increase physical activity.
Obesity of the first degree is defined as BMI 30-34.9 kg/m². This is a serious condition that significantly increases the risk of developing diabetes, hypertension and other diseases. Consultation with a doctor is necessary to develop a weight loss strategy.
Second degree obesity is defined as a BMI of 35-39.9 kg/m². This condition requires a comprehensive approach to weight management under the supervision of specialists. High risk of health complications.
Obesity III degree (morbid obesity) is defined as BMI ≥40 kg/m². This is a critical condition that requires immediate medical intervention and comprehensive treatment under medical supervision.
BMI does not take into account muscle mass, so athletes with developed muscles may have an overestimated index. Muscle is heavier than fat, so an athlete with a normal body fat percentage may have a BMI in the overweight range.
A high BMI (especially above 30) is associated with an increased risk of developing type 2 diabetes, cardiovascular disease, hypertension, some cancers, and musculoskeletal diseases.
It is recommended to check BMI once a month when your weight is stable and more often during an active weight change program. Regular monitoring helps track progress and promptly adjust your approach to nutrition and physical activity.
For children and adolescents, special BMI charts are used taking into account age and gender (centile tables). The standard BMI formula is for adults 18 years of age and older.
A high BMI may indicate a metabolic disorder. In obesity, insulin resistance is often observed, which can lead to the development of metabolic syndrome. A low BMI may also indicate metabolic problems.
Visceral fat is the fat surrounding the internal organs. BMI does not differentiate between visceral and subcutaneous fat. Even with a normal BMI, there can be a high percentage of visceral fat, which increases the risk of disease.
To safely reduce BMI, gradual weight loss of 0.5-1 kg per week is recommended through a balanced diet with a calorie deficit, regular physical activity and lifestyle changes. Consultation with a doctor is required.
To increase BMI if you are underweight, it is recommended to increase your caloric intake with an emphasis on healthy foods, strength training to build muscle mass, and consultation with a doctor to rule out medical causes of underweight.
For older people (over 65 years old), the acceptable BMI range is slightly higher - 23-28 kg/m². This is due to age-related changes in body composition. However, it is important to consider your general health and your doctor's recommendations.
Yes, research shows that a BMI in the range of 18.5-24.9 is associated with the longest life expectancy. A significant deviation in any direction (underweight or excess weight, obesity) can reduce life expectancy.
The goal of losing weight should be to achieve a normal BMI in the range of 18.5-24.9. The specific target value depends on individual characteristics, age, gender and doctor's recommendations. It's important to lose weight to a healthy range, not a minimum.
Metabolic age reflects metabolic rate compared to chronological age. A high BMI may indicate a slower metabolism and increased metabolic age. However, these are different indicators, measured differently.
BMI shows the ratio of weight to height, and percentage of body fat shows the proportion of adipose tissue in total body weight. BMI does not take into account body composition, so a person with a normal BMI may have a high percentage of body fat (especially if they have low muscle mass).
Pre-pregnancy BMI is used to determine weight gain during pregnancy. The recommended weight gain depends on the initial BMI: with normal BMI - 11.5-16 kg, with excess BMI - 7-11.5 kg, with obesity - 5-9 kg.
BMI is directly related to calorie balance. For normal BMI, a balanced diet with adequate calories is important: calorie deficit for weight loss, excess for weight gain, balance for maintenance. The quality of food is also important.
The ideal BMI for health is in the range of 20-25 kg/m². Within this range, the optimal value is individual and depends on age, gender, heredity, level of physical activity and other factors.
No, by definition, BMI cannot be low in obesity. However, there may be a situation where a person with a normal BMI has a high percentage of body fat (especially visceral fat), which is sometimes called "obese at normal weight."
BMI can influence the effectiveness of training. If you have a high BMI, cardio may be more effective at burning calories. When you have a low BMI, it is important to combine training with adequate nutrition to gain muscle mass.
BMI calculator results should be interpreted taking into account age, gender, physical activity level, muscle mass and overall health. BMI is a starting point, but not a definitive diagnosis. In case of deviations from the norm, consultation with a doctor is important.
Yes, there are alternatives: body fat percentage (measured by bioimpedance or caliper), waist circumference, waist-hip ratio, body composition analysis (DEXA). These methods are more accurate, but BMI remains the most accessible screening tool.
To maintain a normal BMI, consistent healthy habits are important: a balanced diet, regular physical activity, adequate sleep, stress management, and regular weight monitoring. It's not a short-term diet that's important, but lifestyle changes.