Ideal Weight Calculator
Calculate your ideal body weight using multiple scientific formulas
How to Use This Ideal Weight Calculator
- Select your gender (formulas differ for men and women)
- Enter your height using cm, inches, or feet/inches
- Click 'Calculate Ideal Weight' to see results from all formulas
- Compare the different formula results and BMI-based range
Example: A 5'10" male gets: Hamwi 166 lbs, Devine 161 lbs, Robinson 162 lbs, Miller 163 lbs. The average across formulas is 163 lbs, while the healthy BMI range is 132-174 lbs.
Tip: Don't fixate on one formula's result. The average of all formulas gives a reasonable target, and anywhere in the healthy BMI range is medically acceptable.
Why Use a Ideal Weight Calculator?
Ideal weight formulas were developed by researchers to estimate appropriate body weight for medication dosing, but they're now widely used for fitness goal-setting.
- Get a specific weight target rather than just a range
- Compare different scientific approaches to ideal weight estimation
- Set an initial goal weight for a weight loss or gain program
- Understand how various medical formulas assess your ideal weight
- Calibrate expectations when starting a new fitness journey
- See how your current weight compares to formula-based ideals
Understanding Your Results
You'll see results from four established formulas plus a BMI-based healthy range. Each formula produces a different number based on its underlying assumptions.
| Result | Meaning | Action |
|---|---|---|
| All formulas agree (within 5 lbs) | Strong consensus on your ideal weight | Use the average as your target; adjust based on your body composition |
| Formulas diverge significantly (10+ lbs spread) | Your height is outside typical ranges where formulas agree | Focus on the BMI range; consult a professional for personalized guidance |
| Current weight far from formula results | Significant difference from calculated ideals | Set intermediate goals; losing 5-10% body weight provides major health benefits |
Meaning: Strong consensus on your ideal weight
Action: Use the average as your target; adjust based on your body composition
Meaning: Your height is outside typical ranges where formulas agree
Action: Focus on the BMI range; consult a professional for personalized guidance
Meaning: Significant difference from calculated ideals
Action: Set intermediate goals; losing 5-10% body weight provides major health benefits
Note: These formulas were developed decades ago using limited populations. They don't account for muscle mass, body frame, or ethnicity. Use them as rough guides, not absolute targets.
About Ideal Weight Calculator
Formula
Base Weight + (Increment × inches over 5 feet) For example, Devine formula for men: 50 kg + 2.3 kg per inch over 5 feet. A 5'10" man: 50 + (2.3 × 10) = 73 kg (161 lbs).
Current Standards: No single formula is universally accepted. The WHO recommends using BMI range (18.5-25) rather than a single ideal weight. These formulas remain popular for their simplicity but should be considered alongside body composition measures.
Frequently Asked Questions
Which ideal weight formula is most accurate?
No single formula is 'most accurate' because ideal weight depends on individual factors these formulas can't capture. The Robinson formula tends to give lower estimates and may be more appropriate for smaller-framed individuals, while Miller tends higher. For most people, the average of all four formulas is a reasonable starting point, but body fat percentage is a better indicator of health than scale weight.
Why do the formulas give different results?
Each formula was developed using different study populations and methodologies. Hamwi used clinical observations, Devine extrapolated from limited data, and Robinson/Miller attempted corrections based on newer research. They also use different increments per inch of height, which causes results to diverge more as height increases or decreases from average.
I'm muscular - should I ignore these formulas?
Partially, yes. These formulas assume average body composition. If you strength train regularly and have above-average muscle mass, your healthy weight could be 10-20+ pounds above formula results. A 180-lb person with 15% body fat is healthier than a 160-lb person with 30% body fat, even if the formulas say 160 is 'ideal.' Consider body fat percentage instead.
Why doesn't age factor into these calculations?
The original formulas didn't include age adjustments. Research since then suggests that slightly higher weights may be protective in older adults (65+), while younger adults benefit from staying in the lower-middle part of the healthy range. If you're over 50, the higher end of formula results or BMI range may be more appropriate.
How is the BMI range different from the formula results?
The BMI range calculates what weights produce a BMI between 18.5 and 25 for your height - this is a range, not a single number. The formulas try to pinpoint an 'ideal' single value. The BMI range is actually more useful because it acknowledges healthy variation in body types. Your ideal might be anywhere within that range.