BMI Calculator
Calculate your Body Mass Index, BMI category, healthy BMI range, and estimated healthy weight range.
years
kg
cm
Your BMI
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BMI Range
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Healthy BMI
Underweight
Normal
Overweight
Obesity
Healthy weight range for your height
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Adult BMI Categories
| Category | BMI Range |
|---|---|
| Underweight | Below 18.5 |
| Normal weight | 18.5 – 24.9 |
| Overweight | 25.0 – 29.9 |
| Obesity | 30.0 or higher |
BMI Formula
BMI = Weight (kg) ÷ Height² (m²)
This calculator is designed for adults aged 20 and older. BMI is a screening measure and does not directly measure body fat. BMI should be considered alongside other health factors and is not a substitute for professional medical advice.
BMI Calculator
Wondering what your BMI is? Our BMI Calculator makes it easy to calculate your Body Mass Index using your height and weight. Enter your age, choose your preferred unit system, and get your BMI result along with your BMI category, healthy BMI range, and estimated healthy weight range.
You can use the calculator with kilograms and centimeters or pounds, feet, and inches, so there is no need to convert your measurements manually.
What Is BMI?
BMI stands for Body Mass Index. It is a simple measurement that compares a person's weight with their height.
BMI is commonly used as a screening measure to classify adult weight into categories such as underweight, normal weight, overweight, and obesity.
BMI does not directly measure body fat, muscle mass, or overall health. For example, someone with a high amount of muscle may have a higher BMI even though they have relatively little body fat. This is why BMI is best considered alongside other factors such as body composition, waist circumference, lifestyle, and overall health.
How to Calculate BMI
The standard BMI formula is:
BMI = Weight (kg) ÷ Height² (m²)
For example, if someone weighs 70 kg and is 175 cm tall:
- Weight = 70 kg
- Height = 1.75 m
- BMI = 70 ÷ (1.75 × 1.75)
- BMI ≈ 22.9
You don't need to perform the calculation yourself. Enter your height and weight into our BMI calculator and it will calculate the result automatically.
Calculate BMI Using kg and cm
If you normally use the metric system, select Metric (kg, cm).
Enter:
- Your age
- Your weight in kilograms
- Your height in centimeters
Then select Calculate BMI.
The calculator will show your BMI, BMI category, standard BMI range, and an estimated healthy weight range for your height.
Calculate BMI Using Pounds, Feet and Inches
If you use the imperial system, select Imperial (lb, ft/in).
Enter your:
- Age
- Weight in pounds
- Height in feet
- Height in inches
The calculator converts the measurements internally and calculates your BMI.
This makes it useful if you are looking for a BMI calculator in kg and feet, BMI calculator in pounds, or a BMI calculator that works with feet and inches.
What Is a Healthy BMI Range?
For adults, a BMI from 18.5 to 24.9 is generally considered the normal-weight range.
This does not mean that every person with a BMI in this range has the same level of health, nor does a BMI outside this range automatically mean that someone is unhealthy.
Age, muscle mass, genetics, lifestyle, medical history, and other factors can all affect health.
BMI Chart
A BMI chart provides a quick way to understand the standard adult BMI categories:
- Underweight: Below 18.5
- Normal weight: 18.5–24.9
- Overweight: 25.0–29.9
- Obesity: 30.0 or higher
The calculator above provides the category automatically after you enter your measurements.
BMI for Women
Women can use the same adult BMI calculator to calculate their BMI from height and weight.
Searches such as BMI calculator for women, female BMI calculator, BMI for women, and healthy BMI for women generally refer to calculating and interpreting BMI using the standard adult BMI categories.
The BMI formula itself is not a separate formula for women and men. However, BMI should always be interpreted in context because it does not account for differences in body composition.
BMI for Men
Men can also use the calculator to calculate their BMI from height and weight.
If you're looking for a BMI calculator for men, male BMI calculator, BMI for men, or a healthy BMI range for men, the adult BMI categories above provide the standard starting point.
As with women, BMI is only one screening measurement and does not directly measure body fat or muscle mass.
BMI by Age
Age is important when interpreting BMI.
The calculator on this page is designed for adults aged 20 and older. BMI interpretation for children and teenagers is different because their bodies are still growing and changing.
For people under 20, BMI is generally interpreted using age- and sex-specific BMI-for-age growth charts rather than the standard adult BMI categories.
This is why you should not use the adult BMI ranges on this page to assess a child or teenager.
Healthy Weight Range Based on Height
BMI can also be used to estimate a healthy weight range for a person's height.
The calculator uses the adult BMI range of 18.5 to 24.9 and calculates the corresponding weight range for your height.
For example, a taller person will generally have a higher weight range than a shorter person while remaining within the same BMI range.
This is more useful than simply asking for one "perfect" weight because healthy weight can vary considerably between individuals.
BMI and Ideal Weight
People often search for terms such as ideal weight calculator, ideal body weight, ideal weight for height, and healthy weight calculator.
There isn't one universally correct weight for every person of a particular height. BMI can provide a general reference range, but it should not be treated as a precise target weight.
Our calculator therefore shows an estimated healthy weight range based on the standard adult BMI range rather than claiming that there is one perfect weight.
What Does a BMI of 18.5 Mean?
A BMI of 18.5 is at the lower boundary of the standard normal-weight range for adults.
A BMI below 18.5 falls into the underweight category according to the standard adult BMI classification.
What Does a BMI of 25 Mean?
A BMI of 25 is just above the standard normal-weight range.
Under the commonly used adult categories, BMI from 25.0 to 29.9 is classified as overweight.
What Does a BMI of 30 Mean?
A BMI of 30 falls into the obesity category under the standard adult BMI classification.
However, BMI alone cannot determine a person's body-fat percentage or overall health. Other measurements and health factors should also be considered.
What Does a BMI of 35 Mean?
A BMI of 35 is within the obesity category according to the standard adult BMI ranges.
If your BMI is significantly above or below the standard range, consider discussing the result with a qualified healthcare professional rather than relying on BMI alone.
Is BMI Accurate for Everyone?
BMI is useful as a general screening measure, but it has limitations.
It does not directly account for:
- Muscle mass
- Body-fat distribution
- Bone density
- Individual body composition
- Some differences between populations
For this reason, BMI should not be used on its own to determine whether someone is healthy.
FAQs
How do I calculate my BMI?
Enter your age, height, and weight into the BMI calculator. Choose Metric or Imperial units and select Calculate BMI. Your BMI and category will be displayed immediately.
What is the BMI formula?
The standard formula is:
BMI = weight in kilograms ÷ height in meters²
What is a normal BMI?
For adults aged 20 and older, a BMI from 18.5 to 24.9 is generally classified as normal weight.
What is a healthy BMI range?
The commonly used healthy or normal BMI range for adults is 18.5–24.9.
Can I calculate BMI in kg and cm?
Yes. Select the Metric option and enter your weight in kilograms and height in centimeters.
Can I calculate BMI using feet and inches?
Yes. Select the Imperial option and enter your weight in pounds and height in feet and inches.
Is BMI different for men and women?
The standard adult BMI formula is the same for men and women. However, BMI does not account for individual differences in body composition, so the result should be interpreted in context.
Does age affect BMI?
Age is important when interpreting BMI. The standard categories on this calculator are intended for adults aged 20 and older. Children and teenagers require age- and sex-specific BMI-for-age interpretation.
Can BMI tell me my body-fat percentage?
No. BMI does not directly measure body fat. It only uses height and weight to produce a screening measurement.
What is the best BMI?
There isn't one exact BMI that is best for every individual. For adults, 18.5–24.9 is generally classified as the normal-weight range, but BMI should be considered alongside other health information.
Should I use BMI to decide whether I need to lose weight?
BMI can be a useful starting point, but it should not be the only factor used to make health or weight-management decisions. If you're concerned about your weight or health, consider speaking with a qualified healthcare professional.
Use Our BMI Calculator
Instead of working through the BMI formula manually, use the calculator above to get your result in seconds.
Enter your age, height, and weight, choose Metric or Imperial units, and select Calculate BMI. You'll see your BMI, category, BMI range, and estimated healthy weight range for your height.
Remember that BMI is a screening measurement rather than a complete picture of your health. Use your result as a starting point and consider it alongside other relevant health information.
