Discover your perfect weight in seconds. Many calculators rely only on one formula (e.g. Devine). But our Calculator, Calculates your ideal weight using five gold‑standard medical formulas (Peterson, Miller, Robinson, Devine, Hamwi). Compares this ideal average to your current weight—so you know exactly how much weight to gain or lose. Displays a clear, easy-to-understand health suggestion, helping you take the right next step.
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Almost everyone has tried to lose weight at some point or knows someone who has. This often stems from the idea of an “ideal” body weight, shaped by what we see on social media, television, movies, and magazines. But what many people don’t realize is that the concept of Ideal Body Weight (IBW) originally had a medical purpose—it was developed to help calculate accurate medication dosages, not to define how someone should look.
Ideal Body Weight (IBW) refers to the estimated weight a person should maintain based on key factors like age, gender, and height. It provides a general guideline for a healthy weight range using well-established formulas such as the Robinson, Miller, Devine, and Hamwi methods. However, IBW is an estimate — it does not account for important individual differences such as muscle mass, bone density, or body fat percentage. This means it is not a perfect or universal measure of health.
While IBW offers a useful starting point, it should be considered alongside other health factors. Conditions like obesity, malnutrition, or heart disease can complicate the relationship between weight and health. Maintaining a weight close to your ideal can reduce the risk of such issues and support overall well-being.
Ideal Body Weight (IBW) formulas were first developed to help calculate accurate drug dosages. They usually start with a base weight for a height of 5 feet, adding a set amount for each additional inch. While the formulas share a similar structure, their exact values differ based on the research behind them. The Devine formula is the most commonly used in clinical practice because of its simplicity and reliability.
Hamwi Formula (1964)
Male: 48.0 kg + 2.7 kg per inch over 5 feet
Female: 45.5 kg + 2.2 kg per inch over 5 feet
Invented for medicinal dosage purposes.
Devine Formula (1974)
Male: 50.0 kg + 2.3 kg per inch over 5 feet
Female: 45.5 kg + 2.3 kg per inch over 5 feet
Similar to the Hamwi Formula, it was originally intended as a basis for medicinal dosages based on weight and height. Over time, the formula became a universal determinant of IBW.
Robinson Formula (1983)
Male: 52.0 kg + 1.9 kg per inch over 5 feet
Female: 49.0 kg + 1.7 kg per inch over 5 feet
Miller Formula (1983)
Male: 56.2 kg + 1.41 kg per inch over 5 feet
Female: 53.1 kg + 1.36 kg per inch over 5 feet
According to the World Health Organization’s (WHO) the healthy Body Mass Index (BMI) range for adults over the age of 18, the recommended healthy BMI range is 18.5 – 25
Here, BMI = weight/height²
All of the above formulas are intended for adults aged 18 and older. For children and adolescents, the Centers for Disease Control and Prevention (CDC) provides age-specific guidelines. According to the CDC, a healthy BMI for children falls between the 5th and 85th percentile for their age group.
Most ideal weight calculators online only tell you how much you should weigh based on your height and age. But this calculator goes one step further. Not only does it calculate your ideal weight using trusted medical formulas, it also compares it with your current weight to tell you if you’re underweight, overweight, or within the healthy range.
What makes this calculator unique is its ability to give you a clear and personalized summary. It tells you exactly how much weight you need to lose or gain, and why that might be important for your overall health. On top of that, it offers simple, helpful advice based on your results—something you don’t often see in standard calculators. The calculator is based on four widely accepted formulas used in medical settings: Devine, Robinson, Miller, and Hamwi. These formulas are trusted by doctors and healthcare professionals to estimate ideal body weight.
Whether you’re just curious or starting a health journey, this tool is designed to be accurate, easy to use, and informative. Just enter your age, height, current weight, and gender—then let the calculator do the rest. It works for both men and women, and you can switch between metric and imperial units based on your preference. In short, this is more than just a number—it’s a smarter, clearer way to understand your body and take the next step toward better health.
