BMI formula
BMI = weightKg / heightMeters²The calculator converts US measurements to kilograms and meters before applying the same formula. Intermediate values are not rounded before the final BMI is displayed.
Adult category ranges
The page uses standard adult screening cut points: below 18.5, 18.5–24.9, 25.0–29.9 and 30 or above. The text label is intentionally descriptive rather than diagnostic.
Healthy-weight range estimate
For the entered height, the calculator rearranges the BMI formula at 18.5 and 24.9 to show the corresponding weight interval. That interval is a mathematical BMI range, not a personalized ideal-weight prescription.
Limitations
BMI does not distinguish muscle, bone and body fat, and it does not represent fat distribution, metabolic health, pregnancy or age-specific needs. This calculator is for adult informational use only.
Frequently asked questions
What is BMI?
Body mass index is weight in kilograms divided by height in meters squared. It is a screening measure, not a direct measurement of body fat or health.
What BMI range does this calculator call healthy weight?
For adults, this page displays the commonly used 18.5 through 24.9 BMI interval as the healthy-weight range. Individual health assessment can require much more context.
Is BMI accurate for athletes?
BMI can classify some muscular people at a higher category because it does not distinguish muscle from body fat. It can also miss other aspects of body composition.
Can children use this BMI calculator?
No. This page is designed for adults. BMI interpretation for children and adolescents depends on age- and sex-specific growth charts rather than the adult categories shown here.
Does a BMI category diagnose a condition?
No. BMI is a screening metric. A category alone does not diagnose a disease, determine fitness, or replace evaluation by a qualified health professional.