What is Body Mass Index (BMI)?

BMI is a simple numerical index of weight-for-height commonly used to classify underweight, normal weight, overweight, and obesity in adults.

What is a normal healthy BMI?

A BMI between 18.5 and 24.9 is considered normal and healthy according to the World Health Organization.

Multiply weight in pounds by 703, then divide by height in inches squared: BMI = (lbs × 703) / (inches²).

No, BMI calculates total body mass. Bodybuilders or muscular athletes may be categorized as overweight despite low body fat.

Select "Metric (cm/kg)" or "Imperial (ft/in/lbs)".

Input your height and current body weight.

Inspect your calculated BMI index number and color-coded status.

Review the recommended healthy weight range for your height.

Body Mass Index is defined as weight in kilograms divided by height in meters squared:

Metric: BMI = weight (kg) / [height (m)]²
Imperial: BMI = 703 × weight (lbs) / [height (in)]²

Metric (cm/kg) and Imperial (ft/in/lbs) unit switching

Standard World Health Organization (WHO) categories

Color-coded health status indicator

Calculates ideal healthy weight range for height

100% private — health data never leaves device

BMI is a screening tool and does not directly measure body fat percentage or muscle mass.
Athletes with high muscle mass may register higher BMI scores despite excellent fitness.

Calculate your college or high school Grade Point Average on a 4.0 weighted scale.

Calculate percentages, exam marks percentage, discounts, and proportion ratios.

Calculate college attendance percentage and find out how many classes you can skip.