Find the body weights that correspond to adult BMI cut-offs at your height.
This calculator converts adult BMI cut-offs into the body weights that correspond to those cut-offs at your height. It shows the weights for BMI 18.5, 25, and 30 so you can see where the adult underweight, overweight, and obesity boundaries fall for a specific height.
Because BMI is calculated from height squared, the weight thresholds change with height. That makes the boundaries personal even though the cut-offs themselves are fixed.
Knowing the actual weight threshold behind a BMI cut-off can make the category easier to interpret. Instead of only seeing a BMI number, you can see the corresponding weight boundary for your height.
Weight at BMI boundary = BMI × Height(m)² BMI boundaries used by this calculator: Underweight: BMI < 18.5 Normal weight: BMI 18.5 - 24.9 Overweight: BMI 25.0 - 29.9 Obese: BMI >= 30.0 For a given height (h) in meters: Underweight threshold = 18.5 × h² Overweight threshold = 25 × h² Obesity threshold = 30 × h²
Result: Overweight threshold: 76.6 kg, Your weight: 80 kg (3.4 kg above)
For a height of 1.75 m: Underweight threshold = 18.5 × 1.75² = 56.7 kg. Overweight threshold = 25 × 1.75² = 76.6 kg. Obesity threshold = 30 × 1.75² = 91.9 kg. At 80 kg, BMI = 26.1, which places the individual 3.4 kg above the overweight boundary and 11.9 kg below the obesity boundary.
The adult BMI categories use fixed cut-offs for underweight, healthy weight, overweight, and obesity. This calculator converts those cut-offs into the corresponding weights for a given height.
Because BMI is weight divided by height squared, taller people have higher absolute weight thresholds at the same BMI value. The boundaries are the same; the converted weights change with height.
The thresholds are reference points for adults rather than a diagnosis. BMI does not measure body composition directly, so the result is most useful when viewed alongside other measures such as waist circumference.
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This page rearranges the standard adult BMI formula to solve for weight at the underweight, overweight, and obesity cut-offs. It uses BMI 18.5, 25.0, and 30.0 with the entered height, then converts the result into the selected unit system. The calculator is intended for adult reference use only.
BMI is weight divided by height squared, so taller people have higher weight thresholds at the same BMI value.
No single BMI boundary is a biological cliff. The cut-offs are useful reference points, but health risk changes gradually rather than in a sudden jump at one exact number.
Yes. BMI cannot distinguish muscle from fat, so muscular adults can cross the overweight threshold while still having low body fat.
That range is classified as overweight for adults. It is a category boundary, not a diagnosis on its own.
Not necessarily. The calculator shows the full range; the best target depends on your overall health and body composition.
It shows the range of weights within the healthy BMI category for your height. It is a reference range rather than a single ideal number.