Overweight Calculator
Find how much weight to lose to reach a normal BMI.
See how much weight would bring you to the top of the healthy BMI range. Informational only.
How the Math Works
The Overweight Calculator uses the Body Mass Index (BMI) formula to determine a healthy weight range. BMI is calculated as weight divided by height squared (kg/m²). To find the maximum healthy weight, we rearrange the formula to weight = BMI × height². By setting BMI to 25 (the upper limit of the 'normal' range), the formula becomes healthy max weight = 25 × height², where height is in meters. This provides a target weight based on your height alone.
Practical Applications
To use the calculator, first measure your height in meters and input it into the formula. Multiply your height squared by 25 to find your maximum healthy weight. Subtract your current weight from this value to determine how much weight you need to lose. For example, if you are 1.7 meters tall, your healthy max weight is 25 × 1.7² = 72.25 kg. If you weigh 80 kg, you’d need to lose 7.75 kg to reach the target.
Day-to-Day Use
This calculation helps set realistic weight loss goals by providing a clear numerical target. It simplifies decision-making for diet and exercise plans, allowing you to track progress toward a healthier BMI. While it doesn’t account for muscle mass or body composition, it serves as a useful starting point for discussions with healthcare professionals and motivates sustainable lifestyle changes.
Worked example
90 kg, 175 cm (BMI 29.4) → lose ~13.4 kg.
FAQ
Is BMI everything?
No — muscle, frame and health markers matter too.