Reverse BMI Calculator

A Reverse BMI Calculator determines the weight you need to achieve a specific BMI target. Unlike standard BMI calculators that compute BMI from weight and height, this tool works backward - you input your desired BMI and height to find the corresponding weight.

The formula is rearranged from the standard BMI formula:

Weight = BMI × (Height in meters)²

For imperial units: Weight (lbs) = BMI × (Height in inches)² ÷ 703

The World Health Organization defines these BMI categories:
• Underweight: Below 18.5
• Normal weight: 18.5 - 24.9
• Overweight: 25 - 29.9
• Obese: 30 and above

While BMI is a useful screening tool, it doesn't account for muscle mass, bone density, or body composition. Athletes may have higher BMI due to muscle, not fat. Reverse BMI provides a theoretical target weight, but consult a healthcare provider for personalized advice.

Use our calculator to find out! Enter your current weight along with your target BMI (e.g., 22 for the middle of normal range) and height. The difference between your current weight and target weight shows how much to lose or gain.

Absolutely! Enter a target BMI in the normal range (18.5-24.9) that's higher than your current BMI. The calculator will show how much weight you need to gain to reach a healthier BMI.

Standard BMI calculates your current BMI from your weight and height. Reverse BMI calculates the weight needed to achieve a target BMI - useful for setting realistic weight loss or gain goals based on healthy BMI ranges.

Healthy weight loss is typically 1-2 lbs (0.5-1 kg) per week. Weight gain should also be gradual at 0.5-1 lb per week. Always consult a healthcare provider before starting any weight management program.