Ideal Weight Calculator
Find your healthy weight range using five scientifically-backed formulas. Compare Robinson, Miller, Devine, Hamwi, and BMI-based calculations side by side to discover your true ideal weight range.
Your Details
Adjusts results based on bone structure
See Your Ideal Weight Range
Enter your details and click calculate to compare results from 5 scientific formulas.
Your Recommended Range
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Based on the consensus of all five formulas, adjusted for your frame size.
Formula Comparison
Consensus Range
The overlap where most formulas agree represents the most reliable range for your height and gender.
Detailed Breakdown
Each formula's result with frame size adjustment applied
| Formula | Ideal Weight | Year |
|---|
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Join NutrifyMI WaitlistUnderstanding Ideal Weight Formulas
The Five Formulas Explained
Devine Formula (1974)
Originally developed by Dr. B.J. Devine for drug dosage calculations. Despite being the oldest formula here, it remains widely used in medicine. It tends to give higher values for taller men and lower values for shorter women.
Hamwi Formula (1964)
Created by Dr. G.J. Hamwi as a quick clinical reference. It tends to produce the widest range of values and gives notably higher estimates for taller individuals, making it less accurate at extremes of height.
Robinson Formula (1983)
Developed by Dr. J.D. Robinson as a refinement of the Devine formula. It's considered one of the more balanced formulas and is widely referenced in medical literature. It generally produces moderate estimates.
Miller Formula (1983)
Created by Dr. D.R. Miller, this formula tends to yield the highest ideal weight values, particularly for shorter individuals. It narrows the gap between male and female estimates compared to other formulas.
BMI-Based Range (18.5 - 24.9)
Rather than a single value, Body Mass Index gives you a healthy weight range. A BMI between 18.5 and 24.9 is considered normal by the WHO. This is the most flexible approach, but doesn't account for muscle mass, bone density, or body composition.
Which Formula Is Most Accurate?
No single formula is universally "best." Each was developed using different population data and methodologies. The Robinson formula is often considered the most balanced for average-height adults, while the BMI range provides the most flexibility.
The real value comes from comparing all five formulas. Where they overlap and agree is likely your most reliable ideal weight range. This is why we highlight the consensus range in your results.
Keep in mind that these formulas only consider height and gender. They do not account for age, muscle mass, bone density, ethnicity, or body fat distribution. Athletes, elderly individuals, and people with higher muscle mass may have an ideal weight outside these ranges.
What Is Frame Size?
Frame size refers to your bone structure. People with larger frames naturally carry more bone and muscle mass, which affects their ideal weight. A simple way to estimate your frame:
Wrist measurement method:
Wrap your thumb and middle finger around your opposite wrist.
- Small frame: Fingers overlap
- Medium frame: Fingers just touch
- Large frame: Fingers don't touch
Our calculator adjusts ideal weight by -10% for small frames and +10% for large frames, which aligns with standard clinical guidelines.
Healthy Weight vs. Ideal Weight
Ideal weight from formulas is a single target number based on population averages. It's a useful reference point but not a rigid goal.
Healthy weight is a broader range where your risk of weight-related health issues is lowest. The BMI range of 18.5 to 24.9 defines this window, but your personal healthy weight also depends on body composition, fitness level, and medical history.
Rather than fixating on one number, aim to be within the consensus range shown in your results. If you're close but not exact, your health metrics (blood pressure, blood sugar, cholesterol) are better indicators of your overall well-being.
Why Does Ideal Weight Vary So Much?
You might notice the formulas give different results, sometimes varying by several kilograms. This happens because:
- Each formula was developed using different study populations
- Some prioritize clinical use (drug dosing) while others focus on health outcomes
- Body composition science has evolved significantly since the 1960s
- No simple formula can capture the full complexity of human bodies
This variation is actually useful. It shows that "ideal weight" is genuinely a range, not a single number. The spread between formulas gives you a realistic window to aim for.