Ideal Weight Calculator

Finding Your Ideal Body Weight

Ideal weight calculations provide target ranges based on height, gender, and frame size. CalcSolver's ideal weight calculator uses multiple established formulas to give you a range rather than a single number, since individual variation is significant. No formula can account for every factor — muscle mass, bone density, and body composition all influence what constitutes a healthy weight for you.

BMI-Based Formulas Explained

Hamwi Formula (1964): For males: 48.0 kg + 2.7 kg per inch over 5 feet. For females: 45.5 kg + 2.2 kg per inch over 5 feet. A 5'10" male would have an ideal weight of 48.0 + (10 × 2.7) = 75.0 kg. This formula was originally developed for medication dosing calculations.

Devine Formula (1974): For males: 50.0 kg + 2.3 kg per inch over 5 feet. For females: 45.5 kg + 2.3 kg per inch over 5 feet. The same 5'10" male would be 50.0 + (10 × 2.3) = 73.0 kg. Devine is the most widely used formula in clinical settings and is the default for many medical applications.

Robinson Formula (1983): For males: 52 kg + 1.9 kg per inch over 5 feet. For females: 49 kg + 1.7 kg per inch over 5 feet. For our 5'10" male: 52 + (10 × 1.9) = 71.0 kg. Robinson tends to produce slightly lower estimates than Devine.

Miller Formula (1983): For males: 56.2 kg + 1.41 kg per inch over 5 feet. For females: 53.1 kg + 1.36 kg per inch over 5 feet. Miller produces the highest estimates among the four formulas and may be more appropriate for individuals with larger frames.

Healthy Weight Ranges

The World Health Organization defines healthy BMI as 18.5-24.9. For a 170cm person, this translates to approximately 53.5-72.0 kg. For 180cm: 59.9-80.7 kg. These ranges provide a broader context than single-formula estimates. Your position within the range should account for age, sex, ethnicity, and activity level. Athletes and active individuals often sit at the higher end of the healthy range or slightly above while maintaining excellent health markers.

Real-World Examples

Athletic Build: A 180cm male who strength trains regularly may weigh 85 kg with 15% body fat. While technically "overweight" by BMI standards, this individual has excellent cardiovascular health and body composition. The formulas were not designed for muscular individuals.

Older Adults: A 70-year-old woman at 160cm may healthily weigh 60-65 kg. Research suggests that slightly higher weights in older adults (BMI 25-27) correlate with better outcomes than lower weights, possibly due to energy reserves during illness.

Growing Teens: Ideal weight formulas are designed for adults and should not be applied to children or adolescents, who use age- and sex-specific growth charts. A 15-year-old's healthy weight depends heavily on their growth stage and trajectory.

Limitations of Ideal Weight Formulas

These formulas have significant limitations: they do not account for body frame size (small, medium, large), muscle mass, fat distribution, ethnicity, or age. They were developed primarily using data from specific populations and may not accurately represent all body types. The formulas produce a single "ideal" number, but healthy weight is actually a range that varies by individual. Use these estimates as a starting reference point, not a definitive target.

Body Composition Importance

Body composition — the ratio of fat mass to lean mass — matters more than total weight. Two people at the same height and weight can have vastly different health profiles based on their body fat percentage. Healthy body fat ranges are typically 10-20% for men and 18-28% for women. Regular exercise that builds muscle while reducing fat improves body composition even when the scale does not change.

Tips and Best Practices

• Use multiple metrics: Do not rely on ideal weight alone. Combine it with BMI, waist circumference, body fat percentage, and blood work results for a complete health picture.
• Weigh yourself consistently: If tracking weight, weigh at the same time each day (morning, after using the bathroom, before eating) for the most consistent readings. Daily fluctuations of 1-2kg are normal due to water retention.
• Focus on trends, not daily numbers: Weight naturally fluctuates day to day. Look at weekly or monthly averages to identify real trends rather than reacting to single weigh-ins.
• Prioritize strength training: Building muscle mass through resistance training improves body composition, boosts metabolism, and supports bone health. Two to three sessions per week is sufficient for most people.
• Consult healthcare professionals: Ideal weight formulas are estimates. A doctor or registered dietitian can provide personalized guidance based on your medical history, genetics, and health goals.

Use CalcSolver's BMI calculator to check your body mass index, the body fat calculator for composition estimates, the BMR calculator for daily calorie needs, and the calorie calculator to plan nutrition for your weight goals.