Ideal Weight Calculator
| Robinson Formula (1983) | 0 lbs |
| Miller Formula (1983) | 0 lbs |
| Devine Formula (1974) | 0 lbs |
| Hamwi Formula (1964) | 0 lbs |
The "Magic Number" Myth
Ask ten different people how much they "should" weigh, and you will get ten different answers. The truth is, there is no single perfect number for every human being.
Your ideal weight depends on a variety of factors including muscle mass, bone density, and frame size. That is why this calculator provides a Range rather than a single digit.
Understanding the 4 Formulas
Our tool doesn't just guess; it uses the four most respected equations used by doctors and researchers worldwide. You will notice they give slightly different results.
1. The Devine Formula (1974)
This is the most widely used formula in the medical community. Doctors often use it to calculate dosage for medications.
- Men: 50kg + 2.3kg per inch over 5 feet.
- Women: 45.5kg + 2.3kg per inch over 5 feet.
2. The Robinson Formula (1983)
Developed to refine the Devine formula using updated population data. It often results in slightly lower weight targets for women.
3. The Hamwi Formula (1964)
This is the easiest one to memorize (The "Rule of 5s").
- Men: 106 lbs for first 5 ft + 6 lbs for each extra inch.
- Women: 100 lbs for first 5 ft + 5 lbs for each extra inch.
Ideal Weight vs. BMI
You might be wondering, "Why do I need this calculator if I already know my BMI?"
BMI (Body Mass Index) is a diagnostic tool used to screen for health risks. It gives you a score (like 22.5).
Ideal Body Weight (IBW) gives you a tangible goal (like 150 lbs). It helps you visualize where you want to be.
When to Ignore These Numbers
These formulas were created based on statistical averages. They do not account for muscle mass. If you are an athlete or bodybuilder, these formulas will likely tell you that you are "overweight." In that case, you should rely on Body Fat Percentage instead.