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BMI Calculator.
Calculate your Body Mass Index and understand your weight category. Your data automatically syncs with the Calorie Calculator.
You are within a healthy weight range. Keep it up!
Frequently Asked Questions
How to calculate BMI?
BMI (Body Mass Index) is your weight in kilograms divided by the square of your height in meters (kg/m²). In imperial units, divide your weight in pounds by your height in inches squared, then multiply by 703. On Calculator Proof, just enter your height and weight in either system and the BMI calculator does the math instantly — showing your score, category, and healthy weight range.
What is a good BMI for your age and weight?
For adults aged 20 and over, the same BMI ranges apply at every age: 18.5–24.9 is considered a healthy or normal BMI, 25–29.9 is overweight, and 30 or above is obese; below 18.5 is underweight. A "good" BMI means staying within the 18.5–24.9 range for your height and weight. Children and teenagers use age- and sex-specific percentile charts instead of adult ranges.
What is a normal BMI?
A normal (healthy) BMI falls between 18.5 and 24.9 kg/m². It means your weight is appropriate for your height and is linked to a lower risk of weight-related health problems. Use the Calculator Proof BMI calculator to get your score and see which category you fall into.