Ideal Weight Calculator: Find Your Healthy Target Weight
An ideal weight calculator estimates optimal body weight ranges using validated formulas including Devine, Robinson, Miller, and Hamwi equations that account for height, sex, and body frame size, enabling individuals to establish realistic weight targets supported by medical research, assess current weight status relative to scientifically-based healthy ranges, set achievable goals for weight management programs grounded in anthropometric standards, and understand that ideal weight represents approximations varying with individual factors including muscle mass, bone density, body composition, and genetic predisposition rather than absolute prescriptive values applicable universally across diverse populations and body types.
Ideal Weight Calculators
Calculate Ideal Weight (Multiple Formulas)
Devine, Robinson, Miller, and Hamwi methods
About These Formulas:
- Devine (1974): Most widely used formula
- Robinson (1983): Modified Devine formula
- Miller (1983): Alternative modification
- Hamwi (1964): Original clinical formula
Healthy Weight Range (BMI-Based)
Weight range for BMI 18.5-24.9
Ideal Weight by Body Frame
Adjusted for small, medium, or large frame
Frame Size Guide:
Measure wrist circumference with thumb and middle finger:
- Small: Fingers overlap significantly
- Medium: Fingers just touch
- Large: Fingers don't touch
Understanding Ideal Weight
Ideal weight represents estimated optimal body mass for a given height based on population health data correlating body weight with mortality rates, disease risk, and functional health outcomes. Multiple formulas developed over decades by medical researchers establish baseline weight targets using height as the primary variable, with adjustments for biological sex reflecting differences in body composition between males and females. The Devine formula, developed in 1974 for pharmaceutical dosing calculations, has become the most widely referenced ideal weight equation, calculating 50 kilograms plus 2.3 kilograms per inch over 5 feet for men, and 45.5 kilograms plus 2.3 kilograms per inch over 5 feet for women, producing weight estimates associated with favorable health outcomes in population studies.
Understanding ideal weight calculations provides reference points for weight management goal-setting while recognizing substantial individual variation in healthy weights due to muscle mass, bone density, body frame size, and genetic factors that standard formulas cannot fully capture. A muscular athlete may exceed formula-calculated ideal weight while maintaining excellent health, while someone with minimal muscle mass might fall within ideal weight ranges despite poor body composition. Ideal weight formulas serve as starting estimates requiring adjustment based on body composition assessments, medical evaluations, and individual health markers rather than prescriptive targets applicable universally. The RevisionTown approach emphasizes understanding mathematical foundations of ideal weight calculations while maintaining perspective that healthy weight encompasses ranges influenced by numerous factors beyond height-based formulas, with body composition, metabolic health, physical fitness, and overall wellness providing more comprehensive health assessment than any single number on a scale.
Ideal Weight Formulas
Men:
\[ \text{IBW} = 50 + 2.3 \times (\text{height in inches} - 60) \]
Women:
\[ \text{IBW} = 45.5 + 2.3 \times (\text{height in inches} - 60) \]
Robinson Formula (1983):
Men:
\[ \text{IBW} = 52 + 1.9 \times (\text{height in inches} - 60) \]
Women:
\[ \text{IBW} = 49 + 1.7 \times (\text{height in inches} - 60) \]
Miller Formula (1983):
Men:
\[ \text{IBW} = 56.2 + 1.41 \times (\text{height in inches} - 60) \]
Women:
\[ \text{IBW} = 53.1 + 1.36 \times (\text{height in inches} - 60) \]
Hamwi Formula (1964):
Men:
\[ \text{IBW} = 48 + 2.7 \times (\text{height in inches} - 60) \]
Women:
\[ \text{IBW} = 45.5 + 2.2 \times (\text{height in inches} - 60) \]
Ideal Weight Calculation Example
Calculate ideal weight for: Male, 180 cm tall
Step 1: Convert Height to Inches
\[ \text{Height} = \frac{180}{2.54} = 70.87 \text{ inches} \]Step 2: Apply Devine Formula (Male)
\[ \text{IBW} = 50 + 2.3 \times (70.87 - 60) \] \[ \text{IBW} = 50 + 2.3 \times 10.87 \] \[ \text{IBW} = 50 + 25.0 = 75.0 \text{ kg} \]Step 3: Apply Other Formulas
Robinson:
\[ \text{IBW} = 52 + 1.9 \times 10.87 = 72.7 \text{ kg} \]Miller:
\[ \text{IBW} = 56.2 + 1.41 \times 10.87 = 71.5 \text{ kg} \]Hamwi:
\[ \text{IBW} = 48 + 2.7 \times 10.87 = 77.3 \text{ kg} \]Results Summary:
- Devine: 75.0 kg
- Robinson: 72.7 kg
- Miller: 71.5 kg
- Hamwi: 77.3 kg
- Average: 74.1 kg
- Range: 71.5 - 77.3 kg
Interpretation: Ideal weight estimates for a 180 cm male range from 71.5-77.3 kg depending on formula, with average around 74 kg.
BMI-Based Healthy Weight Ranges
Body Mass Index provides an alternative approach to determining healthy weight ranges by identifying weights producing BMI values between 18.5 and 24.9—the range associated with lowest mortality risk in population studies. Unlike single-value ideal weight formulas, BMI-based ranges acknowledge acceptable weight variation for any given height.
Minimum Healthy Weight (BMI 18.5):
\[ \text{Min Weight} = 18.5 \times \text{Height (m)}^2 \]
Maximum Healthy Weight (BMI 24.9):
\[ \text{Max Weight} = 24.9 \times \text{Height (m)}^2 \]
Middle of Range (BMI 21.7):
\[ \text{Mid Weight} = 21.7 \times \text{Height (m)}^2 \]
BMI-Based Weight Range Example
For height: 165 cm (1.65 m)
Minimum Healthy Weight (BMI 18.5):
\[ \text{Weight} = 18.5 \times (1.65)^2 = 18.5 \times 2.72 = 50.4 \text{ kg} \]Maximum Healthy Weight (BMI 24.9):
\[ \text{Weight} = 24.9 \times (1.65)^2 = 24.9 \times 2.72 = 67.8 \text{ kg} \]Middle of Range (BMI 21.7):
\[ \text{Weight} = 21.7 \times (1.65)^2 = 21.7 \times 2.72 = 59.1 \text{ kg} \]Healthy Weight Range: 50.4 - 67.8 kg
Range Span: 17.4 kg (34% variation)
Interpretation: A 165 cm individual can maintain healthy BMI anywhere within a substantial 17-kilogram range, allowing for individual differences in body composition and frame size.
Body Frame Size Adjustments
Body frame size reflects skeletal structure and bone mass variations affecting ideal weight independent of height. Individuals with larger frames naturally carry more weight through heavier bone structure and broader skeletal proportions, while small-framed individuals have lighter skeletons requiring less muscle and tissue mass for structural support.
Determining Body Frame Size
Frame size can be estimated through wrist circumference or elbow breadth measurements:
Wrist Measurement Method: Wrap thumb and middle finger around opposite wrist at narrowest point. Fingers overlapping significantly indicate small frame, fingers just touching suggest medium frame, and fingers not reaching indicate large frame.
Elbow Breadth Method: Extend arm forward with elbow bent 90 degrees, measure distance between prominent bones on either side of elbow, compare to standard tables based on height and sex.
Frame Size Weight Adjustments
| Frame Size | Adjustment | Description |
|---|---|---|
| Small Frame | -10% | Subtract 10% from calculated ideal weight |
| Medium Frame | No adjustment | Use calculated ideal weight as-is |
| Large Frame | +10% | Add 10% to calculated ideal weight |
Frame Size Adjustment Example
Scenario: Female, 170 cm, Devine ideal weight = 63.5 kg
Small Frame Adjustment:
\[ \text{Adjusted Weight} = 63.5 \times 0.90 = 57.2 \text{ kg} \]Medium Frame (No Adjustment):
\[ \text{Weight} = 63.5 \text{ kg} \]Large Frame Adjustment:
\[ \text{Adjusted Weight} = 63.5 \times 1.10 = 69.9 \text{ kg} \]Weight Range by Frame: 57.2 - 69.9 kg (12.7 kg span)
Key Point: Frame size creates substantial variation in healthy weight targets for identical heights, reflecting natural skeletal diversity.
Comparison of Ideal Weight Formulas
| Formula | Year | Original Purpose | Characteristics |
|---|---|---|---|
| Hamwi | 1964 | Quick clinical estimation | Highest estimates, simple mental math |
| Devine | 1974 | Pharmaceutical dosing | Most widely used, moderate estimates |
| Robinson | 1983 | Devine modification | Slightly lower than Devine |
| Miller | 1983 | Devine modification | Lowest estimates among major formulas |
Limitations of Ideal Weight Formulas
Ignores Body Composition
Ideal weight formulas cannot distinguish between muscle and fat mass. A bodybuilder with 90 kilograms of lean, muscular mass at 175 centimeters may significantly exceed formula-calculated ideal weight while maintaining exceptional health. Conversely, someone at calculated ideal weight with minimal muscle and high body fat percentage may face metabolic health risks despite falling within mathematical targets.
Population Averages
Formulas derive from population data reflecting average relationships between height and healthy weight. Individual variation in metabolism, genetics, activity levels, and body composition creates substantial deviation from these averages. Formulas provide starting estimates requiring individualization based on comprehensive health assessment.
Age Not Considered
Standard ideal weight formulas don't account for age-related changes in body composition, with older adults naturally experiencing muscle loss and bone density reduction that may make lower weights appropriate compared to younger individuals of identical height. Some research suggests slightly higher BMI values (23-27) associate with better outcomes in elderly populations.
Ethnicity Differences
Formulas developed primarily using Caucasian populations may not optimally apply to other ethnic groups showing different body proportions and disease risk profiles at identical BMI values. Asian populations, for example, face increased health risks at lower BMI thresholds, suggesting lower ideal weight targets than standard formulas indicate.
Athletic vs Sedentary Individuals
Trained athletes with high muscle mass may optimally weigh significantly more than calculated ideal weights, while sedentary individuals might benefit from weights at the lower end of healthy ranges. Activity level, muscle mass, and fitness goals should inform weight targets beyond formula outputs.
Using Ideal Weight Calculations Appropriately
As Starting Points, Not Absolutes
Treat calculated ideal weights as reference points for goal-setting discussions with healthcare providers rather than prescriptive targets requiring strict adherence. Individual health markers including blood pressure, blood lipids, blood glucose, body composition, and functional fitness provide more comprehensive health assessment than any single weight value.
Consider Multiple Formulas
Different formulas produce varying estimates, typically spanning 5-10 kilograms for any given height. Calculate multiple formulas and consider the average or range rather than fixating on a single value from one equation. This range acknowledges mathematical uncertainty and individual variation.
Incorporate Body Composition
Combine ideal weight calculations with body composition assessment through methods including DEXA scans, bioelectrical impedance, or skinfold measurements. Two individuals at identical heights and weights may have vastly different body compositions—one with high muscle and low fat (excellent), another with low muscle and high fat (concerning).
Focus on Health Markers
Prioritize improvements in health indicators over achieving specific scale numbers. Better cardiovascular fitness, normalized blood pressure, improved lipid profiles, enhanced insulin sensitivity, increased strength, and improved mobility indicate health progress regardless of whether weight matches mathematical ideals.
Set Realistic Goals
If current weight significantly exceeds calculated ideal weight, set intermediate targets rather than attempting to reach ideal weight immediately. Losing 5-10% of body weight produces meaningful health improvements even without reaching ideal weight, with sustainable progress trumping aggressive targets leading to rebound weight gain.
Healthy Weight Ranges by Height
| Height | Healthy Weight Range (BMI 18.5-24.9) | Middle of Range |
|---|---|---|
| 150 cm (4'11") | 41.6 - 56.1 kg | 48.8 kg |
| 160 cm (5'3") | 47.4 - 63.7 kg | 55.6 kg |
| 170 cm (5'7") | 53.5 - 71.9 kg | 62.7 kg |
| 180 cm (5'11") | 59.9 - 80.7 kg | 70.3 kg |
| 190 cm (6'3") | 66.8 - 89.9 kg | 78.3 kg |
Alternative Health Metrics Beyond Weight
Waist Circumference
Waist measurement at navel level assesses abdominal obesity, a key cardiovascular risk factor. Men should maintain waist below 40 inches (102 cm), women below 35 inches (88 cm) for optimal health regardless of total body weight.
Waist-to-Hip Ratio
Dividing waist by hip circumference identifies body fat distribution patterns. Ratios above 0.90 for men or 0.85 for women indicate central obesity carrying elevated health risks even at normal BMI or ideal weight.
Body Fat Percentage
Direct body fat measurement through DEXA, BIA, or skinfold calipers provides superior health assessment compared to weight alone. Healthy ranges: 10-20% for men, 18-28% for women, with athletes often maintaining lower percentages.
Muscle Mass
Sufficient muscle mass supports metabolic health, functional capacity, and healthy aging. Sarcopenia (muscle loss) poses significant health risks independent of body weight. Resistance training and adequate protein intake maintain muscle mass across lifespan.
Fitness Level
Cardiovascular fitness, measured through VO2 max or functional tests, predicts health outcomes independently of body weight. Fit individuals at higher weights often demonstrate better health than unfit individuals at ideal weights.
When to Consult Healthcare Providers
Seek professional medical consultation for:
- Current weight significantly above or below calculated healthy ranges
- Difficulty achieving or maintaining healthy weight despite consistent efforts
- Medical conditions affecting weight (thyroid disorders, PCOS, diabetes)
- Pregnancy, breastfeeding, or family planning considerations
- Eating disorders or disordered eating patterns
- Significant weight changes (gain or loss) without intentional lifestyle modifications
- Desire for medical weight loss interventions or bariatric surgery evaluation
Healthcare providers offer comprehensive assessment including medical history, physical examination, laboratory testing, body composition analysis, and personalized recommendations addressing individual circumstances beyond mathematical formulas.
Important Health Disclaimer
This ideal weight calculator provides educational estimates for general wellness planning and does not constitute medical advice or diagnostic tool. Ideal weight formulas represent population averages that may not appropriately apply to individuals with unique body compositions, medical conditions, athletic training, genetic factors, or other characteristics creating variation from mathematical predictions. Calculated values should never replace professional medical assessment, particularly for individuals with eating disorders, significant obesity, medical conditions affecting weight, pregnancy, children and adolescents, elderly individuals, or athletes with high muscle mass. Consult physicians, registered dietitians, or qualified healthcare providers for personalized weight management guidance, medical evaluation of health risks, and comprehensive assessment considering multiple health factors beyond body weight alone.
