BMI Calculator
Calculate your Body Mass Index. Supports metric and imperial units.
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Frequently Asked Questions
What is a normal BMI?
A BMI between 18.5 and 24.9 is considered normal weight. BMI between 25-29.9 is overweight, and 30+ is obese. However, BMI doesn't account for muscle mass, bone density, or fat distribution.
Is BMI accurate for everyone?
BMI is a screening tool, not a diagnostic. Athletes with high muscle mass may have high BMI but low body fat. For a complete picture, also check waist circumference and body fat percentage.
What is this tool?
BMI (Body Mass Index) is a widely used measurement that estimates body fat based on height and weight. Calculated as weight in kilograms divided by height in meters squared (kg/mยฒ), it classifies individuals into underweight (below 18.5), normal (18.5-24.9), overweight (25-29.9), and obese (30+) categories according to WHO standards.
When to use this tool
Health assessment
Quickly check if your weight falls within a healthy range for your height. BMI is the first screening tool used by doctors to identify potential weight-related health issues.
Weight loss tracking
Monitor your BMI over time as you follow a diet or exercise plan. A gradual BMI change of 0.5-1 point per month indicates a healthy rate of weight loss.
Fitness goal setting
Set realistic target weight goals based on your desired BMI range. For most adults, a BMI between 18.5 and 24.9 is considered healthy.
How to use
- 1
Select unit system
Choose between Metric (kg/cm) and Imperial (lb/in) measurement systems.
- 2
Enter height
Type your height in the selected unit.
- 3
Enter weight
Type your weight in the selected unit.
- 4
View results
See your BMI value, health category, and healthy weight range.
Frequently Asked Questions
Is BMI accurate for everyone?
BMI is a quick screening tool but does not distinguish between muscle and fat mass. Athletes with high muscle mass may show elevated BMI despite being healthy. It works best for general population but should not be the sole health indicator.
What is a healthy BMI range?
WHO normal BMI is 18.5 to 24.9. Asians may have lower thresholds: overweight at 23, obesity at 27.5. Children and teens use BMI percentiles rather than fixed ranges. Older adults may benefit from slightly higher BMI targets.
How often should I check my BMI?
During weight management, check every few months. If weight is stable, annual checks suffice. BMI trends over time are more meaningful than single measurements.