WHAT THIS TOOL IS FOR
This BMI calculator works out body mass index from height and weight.
Use metric inputs in centimetres and kilograms, or imperial inputs in feet, inches, stone and pounds.
BMI is a screening measure, not a full health diagnosis.
HOW TO USE IT
Choose metric or imperial units. Enter your height and weight, then press SOLVE.
The calculator converts the values if needed, applies the BMI formula and shows the adult BMI category.
Use EXAMPLE to restore a safe worked example. Use CLEAR to reset values.
BMI FORMULA
Metric formula: BMI = weight in kg ÷ height in metres squared.
Example: 170 cm is 1.70 m. BMI = 70 ÷ (1.70 × 1.70).
Imperial entries are converted to kg and metres first.
BMI CATEGORIES
Underweight: below 18.5. Healthy: 18.5 to 24.9.
Overweight: 25 to 29.9. Obese: 30 and above.
Adults, children, athletes and pregnant people may need different interpretation.
WORKED EXAMPLE
Height = 170 cm, so height in metres = 1.70 m.
Weight = 70 kg. BMI = 70 ÷ (1.70 × 1.70).
BMI = 24.2, which is in the healthy adult BMI range.
COMMON SEARCHES
BMI calculator, body mass index calculator, BMI calculator kg cm, BMI calculator stone pounds, healthy weight calculator.
Used by adults checking a quick weight-height ratio, students learning the formula, and anyone comparing metric and imperial units.
The calculator stays on page 1. SEO text is split into full-size reading pages.
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This page belongs to the utility calculators section and links to nearby health and utility tools.