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RATED FASTEST Body Mass Index (BMI) Calculator 2025 ๐Ÿ†

Meet Growpopularity's Free Body Mass Index (BMI) Calculator

Based on your height, weight, and age, this tool helps you understand whether you're underweight, at a healthy weight, overweight, or obese. Includes age-based insights and supports both US and metric units. View your results on a dynamic BMI chart and learn your ideal healthy weight range.

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No credit cards needed. Absolutely no cost to you, ever.
Health Monitoring
A BMI calculator helps you keep tracking of your health
Fitness Goals
You can monitor your health improvements more accurately.
Weight Management
Using a BMI calculator can help you maintain a healthy weight.
Health Assessment
This helps you stay fit, active and healthy.

BMI Calculation

How to calculate BMI

To calculate your Body Mass Index (BMI), you'll need to know your weight and height. Once you have these details, you can determine your BMI using the two simple steps outlined below.

Multiply your height by itself (height X height).
Divide your weight by the answer you get in the first step.

The equations for calculating the BMI are as follows:

International System of Units (SI)
BMI = weight (kg) รท (height (m))2

Example:
A 177 cm (1.77 m) individual weighing 75 kg,

BMI = 75 / (1.77 * 1.77) = 75/ 3.13 = 23.96
Imperial System
BMI = weight (lb) รท (height (inches)) 2 ร— 703

Example:
A 160-pound, 5โ€™8โ€ (68โ€) individual weighing 75 kg,

BMI = (160/ 68*68) * 703 = (160/4624) * 703 = 24.3

You can also use an online BMI calculator to find out your BMI and eliminate human errors.


BMI table for adults

This is the World Health Organization's (WHO) recommended body weight based on BMI values for adults. It is used for both men and women, age 20 or older.


Classification BMI range - kg/m2
Severe Thinness < 16
Moderate Thinness 16 - 17
Mild Thinness 17 - 18.5
Normal 18.5 - 25
Overweight 25 - 30
Obese Class I 30 - 35
Obese Class II 35 - 40
Obese Class III > 40

FAQS

You asked, we answered

Got questions about Body Mass Index (BMI) Calculator? You're not alone. We've rounded up your top queries about our calculator and dished out the answers quick, clear, and to the point.

What is the purpose of calculating BMI?
The primary goal of calculating BMI for both men and women is to determine whether an individual's weight falls within a healthy range relative to their height. The BMI calculator provides a numeric value that classifies individuals as underweight, normal weight, overweight, or obese, helping to identify potential health risks. This simple yet effective tool is widely used by individuals, patients, and healthcare professionals to gain a better understanding of overall health and to guide wellness decisions.
Are there any age or gender specific considerations for BMI?
Yes, BMI calculations can be influenced by both age and gender. Although the formula for calculating BMI is the same for men and women, the interpretation of the results may vary due to differences in body composition, muscle mass, and fat distribution. Therefore, understanding how BMI applies differently to men and women is essential for accurate health assessment.
Can BMI be used during pregnancy?
BMI is not typically a reliable tool for evaluating a woman's weight during pregnancy. This is because pregnancy naturally causes changes in weight, body composition, and fat distribution, making BMI less accurate. During this time, it's essential for expectant mothers to consult their healthcare providers, who can use more appropriate methods to monitor both maternal health and fetal development effectively.
What are the limitations of the BMI calculator?
While the BMI formula is a useful indicator of general health status, it comes with certain limitations. A key drawback is that it cannot distinguish between muscle and fat, which can be misleading for athletes or individuals with higher-than-average muscle mass. Additionally, BMI does not consider body fat distribution it cannot differentiate between fat, muscle, or bone mass, nor does it indicate where fat is stored in the body. As a result, it's important to use other health metrics alongside BMI for a more complete and accurate health assessment.
What is a good BMI for a man?
A BMI between 18.5 and 24.9 is generally regarded as normal for most adult men. However, it's important to note that this measurement does not account for muscle mass, fitness level, or individual health conditions, which are crucial for a complete health assessment.
What is a good BMI for a woman?
For most adult women, a BMI between 18.5 and 24.9 is generally considered within the healthy range, similar to men. However, individual factors like muscle mass, fitness level, and underlying health conditions are essential in forming a complete picture of overall health.
Should I ignore my weight and concentrate on my BMI?
It's important not to overlook either your weight or your BMI, as both are key indicators of your overall well-being. While weight is a basic health metric, BMI adds context by evaluating the relationship between your weight and height offering a more complete picture of your health status. For accurate insight into your fitness and wellness, both weight and BMI should be considered together.