What calculators does Fit Body Calculators offer?

Fit Body Calculators offers a wide range of health and fitness calculators including BMI, BMR, TDEE, body fat percentage, macro calculator, ideal weight, and many more.

Are the calculators on Fit Body Calculators free to use?

Yes, all calculators on Fit Body Calculators are completely free to use with no registration required.

How accurate are the fitness calculators?

Our calculators use scientifically validated formulas and provide accurate estimates based on the information you provide. However, they should be used as guidelines rather than absolute values.

BMI Calculator

Calculate your Body Mass Index (BMI) to determine if you are at a healthy weight for your height. BMI is a useful measure of overweight and obesity.

Calculate Your BMI

Enter your weight and height to calculate your Body Mass Index.

Understanding Your BMI

Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is BMI = kg/m² where kg is a person's weight in kilograms and m² is their height in meters squared.

A BMI of 25.0 or more is overweight, while the healthy range is 18.5 to 24.9. BMI applies to most adults 18-65 years.

BMI is an estimate of body fat and a good gauge of your risk for diseases that can occur with more body fat. The higher your BMI, the higher your risk for certain diseases such as heart disease, high blood pressure, type 2 diabetes, gallstones, breathing problems, and certain cancers.

However, BMI doesn't directly measure body fat, so some people, such as muscular athletes, may have a high BMI without having a high percentage of body fat.

Frequently Asked Questions

What is BMI?: Body Mass Index (BMI) is a numerical value of your weight in relation to your height. It is a commonly used indicator to categorize individuals as underweight, normal weight, overweight, or obese. BMI provides a simple and objective way to assess weight status and potential health risks associated with weight.
How is BMI calculated?: BMI is calculated by dividing your weight in kilograms by the square of your height in meters (kg/m²). In imperial units, the formula is: [weight (lbs) × 703] ÷ [height (inches)²]. For example, a person weighing 70kg with a height of 1.75m would have a BMI of 70 ÷ (1.75 × 1.75) = 22.9 kg/m².
What are the BMI categories?: The standard BMI categories for adults are: Underweight (BMI less than 18.5), Normal weight (BMI 18.5-24.9), Overweight (BMI 25-29.9), and Obese (BMI 30 or greater). Obesity is further classified into Class 1 (BMI 30-34.9), Class 2 (BMI 35-39.9), and Class 3 or severe obesity (BMI 40 or greater).
Is BMI accurate for everyone?: BMI has limitations and may not be accurate for everyone. It doesn't distinguish between muscle and fat, so athletes or muscular individuals may have a high BMI despite having healthy body fat levels. It also doesn't account for factors like age, gender, ethnicity, body composition, or fat distribution. BMI should be used as one of several tools to assess health, not as the sole indicator.
How often should I check my BMI?: For most adults, checking BMI once or twice a year during regular health check-ups is sufficient. If you're actively trying to lose or gain weight, you might check more frequently (every 1-3 months) to track progress. However, focus on long-term trends rather than small fluctuations, and consider other health markers alongside BMI.
What should I do if my BMI is outside the normal range?: If your BMI falls outside the normal range (18.5-24.9), consider consulting with a healthcare provider for a more comprehensive health assessment. They can evaluate other factors like waist circumference, body composition, blood pressure, and blood tests to determine if your weight is affecting your health. They can also provide personalized recommendations for diet, exercise, and lifestyle changes if needed.
What are the limitations of BMI?: BMI does not directly measure body fat and doesn't account for factors like muscle mass, bone density, or overall body composition. Athletes with high muscle mass may have a high BMI without excess fat. BMI also doesn't consider age, gender, ethnicity, or fat distribution.
Is BMI accurate for everyone?: BMI is less accurate for athletes, elderly individuals, pregnant women, and certain ethnic groups. It should be used as one of several tools to assess health, alongside measurements like waist circumference, body fat percentage, and other health indicators.
What BMI is considered healthy?: A BMI between 18.5 and 24.9 is generally considered to be in the healthy weight range for adults. However, ideal BMI can vary based on factors like age, gender, and ethnicity.