BMI Calculator

Age

ages: 2 - 120

Gender

Male Female

Height

feet

inches

Weight

pounds

Results:

Fill in the form and click Calculate to see your BMI details.

Know About That Tool

Introduction

Wondering if your weight is healthy for your height? Our BMI calculator helps you find out in seconds. Body Mass Index is a simple measurement that doctors and health professionals use worldwide to assess if someone is underweight, normal weight, overweight, or obese. This tool is useful for adults who want to monitor their health, set fitness goals, or understand their risk for weight related health problems. You just need to enter your age, gender, height, and weight. The calculator works with both US units like feet, inches, and pounds or metric units like centimeters and kilograms. Within seconds, you get your BMI number along with information about what it means for your health. This is a starting point for conversations with your doctor and for making informed decisions about diet and exercise.

How the BMI Calculator Works

Gathering Your Body Measurements

The calculator asks for four pieces of information to give you accurate results. First is your age, which helps provide age appropriate health guidance. Second is your gender, because men and women have different body compositions and health considerations. Third is your height, which you can enter in feet and inches or in centimeters depending on which unit system you prefer. Fourth is your current weight in pounds or kilograms. Make sure you measure your height and weight accurately for the best results. You can weigh yourself in the morning before eating for the most consistent reading.

Calculating Your Body Mass Index

Once you enter all your information and click calculate, the tool uses a standard mathematical formula to compute your BMI. This formula divides your weight by your height squared. The result is a number typically between 15 and 40 for most adults. The calculation is the same formula used by doctors, fitness trainers, and health organizations around the world. Your BMI number falls into one of several categories that indicate whether your weight is in a healthy range. The calculator automatically converts between measurement systems so you always get an accurate result no matter which units you use.

Interpreting Your Results

After calculation, you see your BMI number and which category you fall into. The standard categories are underweight, normal weight, overweight, and obese. Each category comes with different health implications. A BMI below 18.5 suggests you might be underweight. A BMI between 18.5 and 24.9 is considered normal and healthy. A BMI between 25 and 29.9 indicates overweight. A BMI of 30 or higher falls into the obese category. The calculator explains what your result means and may suggest talking to a healthcare provider if your BMI is outside the normal range. Remember that BMI is just one tool and does not account for muscle mass, bone density, or body composition.

Formula Section

BMI Formula for Imperial Units

If you use US measurements, you first convert your height to total inches. For example, 5 feet 10 inches becomes 70 inches. Then you square this number. Multiply your weight in pounds by 703, then divide by your height in inches squared. This gives you your BMI value.

BMI Formula for Metric Units

For metric calculations, convert your height to meters if needed. For example, 175 centimeters becomes 1.75 meters. Square this height value. Then divide your weight in kilograms by this squared height. The metric formula is simpler because it does not need a conversion factor.

Example Section

Calculating BMI for a 25 Year Old Male

Let me walk you through a complete example using US units. Suppose you are a 25 year old male who is 5 feet 10 inches tall and weighs 160 pounds.

First, convert your height to inches. You have 5 feet, which equals 60 inches, plus 10 more inches. Your total height is 70 inches.

Next, square your height. Multiply 70 by 70 to get 4900.

Now take your weight of 160 pounds and multiply by 703. This gives you 112480.

Divide 112480 by 4900 to get approximately 22.96.

Your BMI is 23, which falls in the normal weight category of 18.5 to 24.9.

This result suggests your weight is healthy for your height. You have a lower risk of weight related health problems compared to someone with a BMI in the overweight or obese range.

If the same person weighed 200 pounds instead, the calculation would be 200 times 703 divided by 4900, which equals approximately 28.7. This would put them in the overweight category, suggesting they might benefit from losing some weight through diet and exercise.

FAQ Section

Is BMI an accurate measure of health?

BMI is a useful screening tool but not a complete measure of health. It works well for most adults but has limitations. Athletes with high muscle mass may have a high BMI even though they are very healthy. Older adults may have a normal BMI but low muscle mass. BMI also does not measure where you carry fat, and belly fat is more dangerous than fat in other areas. Use BMI as one factor alongside other health markers.

What is a healthy BMI range?

For most adults, a BMI between 18.5 and 24.9 is considered healthy and normal. This range is associated with the lowest risk of weight related diseases like diabetes, heart disease, and high blood pressure. However, the ideal BMI can vary slightly based on age, ethnicity, and individual body composition. Some Asian populations may have increased health risks at lower BMI levels.

How can I improve my BMI if it is too high?

If your BMI is in the overweight or obese range, you can improve it through a combination of healthy eating and regular physical activity. Focus on eating more vegetables, fruits, whole grains, and lean proteins while reducing processed foods, sugary drinks, and excessive portions. Aim for at least 150 minutes of moderate exercise each week. Even small weight loss of 5 to 10 percent of your body weight can significantly improve your health. Consult with a doctor or dietitian for personalized advice.

Can children use this BMI calculator?

This calculator is designed for adults aged 18 and older. Children and teenagers need different BMI calculations that account for age and sex because their bodies are still growing. Pediatric BMI uses percentiles rather than fixed categories. If you need to calculate BMI for a child, look for a specialized pediatric BMI calculator or consult with your child's doctor.

Related Tools Section

Understanding your BMI is just the first step toward better health. To make real progress, you also need to know how many calories your body needs each day. Our Calorie Calculator helps you determine your daily calorie requirements based on your age, gender, weight, height, and activity level. This tool shows you how many calories to eat for weight loss, maintenance, or muscle gain. Check out the Calorie Calculator at https://calcversa.com/calorie-calculator/ to create a personalized nutrition plan that works with your BMI goals and helps you achieve lasting results.