BMI Calculator

Calculate your body mass index and understand what your result means. For adults age 20 and older.

Calculate your BMI

Enter your details and choose your preferred unit system.

Your BMI

Healthy BMI range

18.5 – 24.9

Estimated healthy weight range

BMI Range Indicator

UnderweightHealthy WeightOverweightObesity

What this means

Your next step

Use your BMI as a starting point and focus on practical habits that support your overall health.

    BMI is a screening measure. Your result does not by itself diagnose a health condition or determine a personal treatment plan.

    Your measurements

    Height
    Weight
    Age

    Understanding Body Mass Index (BMI)

    Body Mass Index (BMI) is a screening measure that uses your height and weight to estimate whether your body weight falls within a commonly used range. It is useful for identifying potential weight-related health risks, but it should not be used as a diagnosis on its own.

    How Is BMI Calculated?

    BMI is calculated by dividing body weight by height squared. The formula differs slightly depending on whether metric or imperial measurements are used.

    Metric Formula

    BMI = Weight (kg) ÷ Height² (m)

    Example: A person weighing 70 kg and measuring 1.75 m tall:

    70 ÷ (1.75 × 1.75) =22.9 kg/m²

    Imperial Formula

    BMI = 703 × Weight (lb) ÷ Height² (in)
    Example: A person weighing 154 lb and measuring 69 inches tall:

    703 × 154 ÷ (69 × 69) = 22.7 kg/m²

    BMI Categories for Adults

    For adults, BMI is commonly classified using the following standard ranges:
    BMI RangeCategory
    Below 18.5Underweight
    18.5 – 24.9Healthy Weight
    25.0 – 29.9Overweight
    30.0 and aboveObesity

    What Does Your BMI Result Mean?

    Your BMI result places you into one of the standard weight categories based on your height and weight. A result outside the healthy range does not automatically mean that you have a health problem. Your BMI should be considered together with factors such as body composition, waist measurement, physical activity, diet and overall health.

    What BMI Can and Cannot Tell You

    BMI is useful because it is simple and quick, but it does not directly measure body fat. It cannot distinguish between muscle, bone and fat, and it does not show where body fat is stored. This means a muscular person may have a higher BMI without having excess body fat.

    BMI and Age

    Standard adult BMI categories are generally used for adults. For children and teenagers, BMI must be interpreted differently because body composition changes as they grow. BMI-for-age references based on age and sex are used instead of adult BMI cutoffs.

    Does BMI Differ for Men and Women?

    The standard numerical BMI categories for adults are the same for men and women. However, BMI does not account for differences in body composition, so the same BMI can represent different amounts of body fat in different people.

    Why BMI Is Only a Screening Tool

    BMI should not be viewed as a complete measurement of health. A more complete assessment may also consider waist circumference, body composition, blood pressure, blood tests, medical history, nutrition, activity level and other individual factors.
    Important: BMI is a screening measure and should not be used by itself to diagnose a medical condition or determine a treatment plan.

    What to Do After Checking Your BMI

    You have your BMI result. What should you actually do with it? BMI can be a useful starting point for understanding your weight in relation to height, but it is only one screening measure. The most useful next step is to look at the everyday habits and other health factors that can influence your weight and overall wellbeing.

    If your goal is to maintain a healthy weight

    A BMI in the commonly used healthy-weight range does not mean you need to keep trying to lower the number. Focus instead on habits that help you maintain a balanced routine over time.

    Build balanced mealsInclude a variety of vegetables, fruits, whole grains and protein-rich foods.
    Stay physically activeChoose regular activities you enjoy and can maintain as part of your routine.
    Support good sleepKeep a consistent sleep routine and give your body enough time to rest.
    Track habits, not just weightNotice changes in activity, eating patterns, sleep and other routines over time.

    If your BMI is outside the commonly used healthy range

    A result outside the healthy-weight range does not automatically mean that you have a health problem. BMI does not distinguish between muscle, bone and fat, and it does not account for every factor that affects health or body weight. Consider the result as a starting point rather than a diagnosis.

    Small, sustainable changes can be more useful than trying to make rapid changes. Depending on your situation, this may include improving food choices, becoming more physically active, improving sleep or reviewing your routine with a qualified healthcare professional.

    Look beyond one number

    Weight-related health is influenced by more than height and weight. Waist measurement, body composition, blood pressure, medical history, nutrition, activity level, sleep and other individual factors may provide additional context. If you have concerns about your weight, unexplained weight changes or an existing health condition, a healthcare professional can help interpret your BMI alongside your individual circumstances.

    A simple VinkaMetrics approach

    Use your result in four steps: calculate your BMI, understand what the number can and cannot tell you, act on practical habits that fit your life, and explore other relevant health metrics when you need more context.

    FAQs

    What is considered a healthy BMI?For most adults, a BMI from 18.5 to 24.9 falls within the commonly used healthy weight range.
    How accurate is BMI?BMI is useful as a general screening measure, but it is not a direct measurement of body fat or overall health. Muscle mass and body composition can affect the result.
    Why can an athlete have a high BMI?Muscle is denser than fat. A highly muscular person can therefore have a higher BMI even when they have relatively low body fat.
    Are BMI ranges different for men and women?The standard adult BMI cutoffs are the same for men and women, but body composition can differ between individuals.
    Can children use adult BMI categories?No. Children and teenagers require age- and sex-specific BMI-for-age interpretation rather than the standard adult categories.
    What should I do if my BMI is outside the healthy range?Consider your result as a starting point rather than a diagnosis. A healthcare professional or qualified dietitian can help interpret your BMI alongside your individual health and lifestyle factors.

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