BMI Calculator
Smart BMI & Targets by checkit.health
What does my BMI mean?
BMI groups adults into ranges: under 18.5 is underweight, 18.5–24.9 is a healthy weight, 25–29.9 is overweight, and 30 and over is in the obesity range. These bands are a screening tool, not a diagnosis.
How is BMI calculated?
BMI is your weight in kilograms divided by your height in metres squared (kg/m²). For example, 70 kg at 1.75 m is 70 ÷ (1.75 × 1.75) ≈ 22.9. This calculator does the maths for you in either metric or imperial units.
Why BMI isn’t always accurate
BMI doesn’t distinguish muscle from fat, so very muscular people can read as “overweight”. It also doesn’t show where fat is stored. It can also read differently across ages and ethnic groups. For a fuller picture, pair BMI with your waist-to-height ratio and body-fat estimate.
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Educational use only. checkit.health calculators provide general information and are not a medical diagnosis or a substitute for professional advice. Always talk to a qualified healthcare professional about your health, symptoms or before making changes to medication, diet or exercise.
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