ToolFoxBMI Calculator
Check your Body Mass Index in metric or imperial units, with the standard WHO category.
How it works
BMI = weight in kilograms ÷ (height in metres)². Imperial inputs are converted first (1 lb = 0.4536 kg, 1 inch = 2.54 cm). WHO categories: under 18.5 is underweight, 18.5–24.9 normal, 25–29.9 overweight, 30+ obese.
Example
At 70 kg and 175 cm, BMI = 70 ÷ 1.75² ≈ 22.9 — in the normal range. The same person at 80 kg would be 26.1, just into overweight.
Frequently asked questions
Is BMI accurate for everyone?
It is a population screening measure — athletes with high muscle mass and older adults can be misclassified. It is not a diagnosis.
Are the cut-offs different in Asia?
Several Asian guidelines use lower thresholds (23 overweight, 27.5 obese) because health risks start at lower BMIs; this tool shows WHO standard bands.
Does age or sex matter?
Adult BMI bands are the same for all; children use age-specific percentile charts that this tool does not cover.
What should I do about my result?
Treat it as a starting point and discuss with a doctor — BMI alone never tells the whole story.
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