BMI Calculator
NewCalculate Body Mass Index from height and weight, with metric and imperial units.
BMI calculator
BMI Calculator
Calculate Body Mass Index from height and weight, with metric and imperial units.
Switch between metric and imperial units to calculate body mass index and see where it falls on a category scale.
Body mass index
Enter height and weight to calculate BMI.
Frequently Asked Questions
Does this adjust BMI for age, sex, or body type?
No. This tool calculates standard BMI from height and weight only, then maps the result to the usual underweight, normal, overweight, and obese bands.
How does imperial mode work behind the scenes?
It converts feet plus inches to meters and pounds to kilograms first, then applies the same BMI formula used in metric mode.
Why does the marker stop moving after very high values?
The visual scale is capped to the 10-40+ range. Very low or high BMI values are still calculated, but the marker position is clamped inside that bar.
Does the BMI value update live while I type?
Yes. As soon as the required fields in the active unit mode are valid, the BMI number, category badge, marker, and explanation update automatically.
What counts as invalid input here?
Height and weight must be positive numbers. In imperial mode, either feet or inches can contribute to height, but the combined height still has to be greater than zero.
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