Calculate your body mass index from height and weight in metric or imperial units, and see which BMI category you fall into. Free online BMI calculator.
Calculate BMI from height and weight using metric or imperial inputs.
How to use BMI Calculator
Choose Metric or Imperial.
Enter height in the displayed units and weight in kilograms or pounds.
Review the BMI result and the tool’s screening category.
Worked example
At 70 kg and 1.75 m, BMI is approximately 22.9 using weight divided by squared height in meters.
Does BMI diagnose health or measure body fat?
No. BMI is a screening measure and does not directly measure body fat or replace an individual health assessment.
Is this an age-specific calculator for children?
No. The interface uses fixed categories and has no age or sex inputs. Children and teens need age-specific interpretation rather than these adult-style labels.
Put this guide into practice
BMI Calculator — Calculate Body Mass Index in metric or imperial units.