How this calculator helps
Calculate Body Mass Index in metric or imperial and read supportive context about what BMI can and cannot tell you.
Inputs used
This page uses simple inputs: Height, Weight, Metric or imperial units. Metric and imperial support lets users choose the unit system that fits their country and preference.
Methodology and formula
BMI is calculated from weight divided by height squared. In metric units, the formula is weight in kilograms divided by height in metres squared.
How to interpret the result
BMI is a simple population-level screening guide. It can be a starting point, but it does not measure body composition, strength, health behaviours or individual health status.
Safety and limitations
BMI does not replace medical advice. It can be less informative for athletes, older adults, pregnant people and anyone with body composition differences.
Information on w8t.ai is for general wellness only and is not medical advice.
Frequently asked questions
What is BMI?
BMI is a simple height-to-weight calculation used as a general population-level screening guide.
Does BMI measure body fat?
No. BMI does not directly measure body fat or body composition.
What if my BMI is above the common range?
BMI is only one guide. Small, steady changes to meals, movement and sleep can be a calmer starting point than strict rules.
Is BMI medical advice?
No. It is general wellness information and does not replace medical advice.