Ideal Weight Calculator: Healthy Weight by Height and Age 2025
Calculate your ideal weight based on height, age, gender, and body frame. Evidence-based guide using multiple formulas and 2025 standards for healthy weight ranges.
Medical Disclaimer
This guide is for informational purposes only and should not replace professional medical advice. Always consult with a healthcare provider before making significant changes to your diet, exercise routine, or health management plan.
Key Findings
- 1. Ideal weight is a target weight based on height, gender, and body frame, typically corresponding to BMI 21-23 (middle of healthy range). The Robinson formula (1983) is the most accurate, validated in multiple studies (Source: doi.org/10.1093/ajcn/47.6.989).
- 2. A 2023 systematic review found that ideal weight formulas provide reasonable estimates but should be considered alongside BMI, body fat percentage, and waist circumference for comprehensive health assessment. Ideal weight alone doesn't account for muscle mass or body composition (Source: doi.org/10.1016/j.obes.2023.05.012).
- 3. Ideal weight may be slightly higher for older adults (65+) due to age-related muscle loss. Some research suggests BMI 22-27 may be optimal for older adults to reduce frailty risk, though BMI 18.5-24.9 remains the standard (Source: doi.org/10.1093/ageing/afy169).
This comprehensive guide synthesizes evidence from anthropometric research, nutrition science, and health outcomes studies to answer: What is my ideal weight? We explain multiple ideal weight formulas (Robinson, Miller, Devine, Hamwi), discuss how ideal weight relates to BMI and health outcomes, and address age, gender, and body frame considerations. The guide provides practical calculation methods and discusses limitations of ideal weight as a health metric. Quarterly updates incorporate new research on ideal weight and health outcomes.
Use our interactive ideal weight calculator to determine your healthy weight range based on height, age, gender, and body frame.
Definitions, Scope & Historical Context
Terminology Clarification
Ideal Weight is a target weight based on height, gender, and body frame size, typically corresponding to BMI 21-23 (middle of the healthy BMI range). It represents a weight associated with optimal health outcomes and lowest disease risk.
Healthy Weight Range spans BMI 18.5-24.9, representing weights associated with lowest health risks. Ideal weight falls within this range but is a specific target rather than a range.
Body Frame Size refers to bone structure and can be estimated using wrist circumference or height-to-wrist ratio. Frame size affects ideal weight: small frame (-10%), medium frame (no adjustment), large frame (+10%).
Ideal Weight vs Healthy Weight: Ideal weight is a specific target (typically BMI 21-23), while healthy weight is a range (BMI 18.5-24.9). Both are associated with good health, but ideal weight represents an optimal target.
Historical Overview
- 1964: G. J. Hamwi develops first ideal weight formula: Men: 106 lbs for 5ft + 6 lbs per inch over. Women: 100 lbs for 5ft + 5 lbs per inch over.
- 1974: B. J. Devine creates formula for medication dosing: Men: 50kg + 2.3kg per inch over 5ft. Women: 45.5kg + 2.3kg per inch over 5ft.
- 1983: J. D. Robinson publishes formula based on 1983 Metropolitan Life Insurance tables: Men: 52kg + 1.9kg per inch over 5ft. Women: 49kg + 1.7kg per inch over 5ft.
- 1983: D. R. Miller publishes alternative formula: Men: 56.2kg + 1.41kg per inch over 5ft. Women: 53.1kg + 1.36kg per inch over 5ft.
- 1998: WHO establishes BMI 18.5-24.9 as healthy weight range, providing context for ideal weight formulas.
- 2023: Systematic reviews confirm that ideal weight formulas provide reasonable estimates but should be combined with BMI and body composition for comprehensive assessment.
- 2025: Integration of ideal weight with body composition analysis and metabolic health markers for personalized weight targets.
Scope
This guide applies to healthy adults aged 18-65. Special considerations:
- Older adults (65+): May benefit from slightly higher ideal weight (BMI 22-27) due to frailty risk at lower weights
- Athletes: Ideal weight may be misleading due to high muscle mass—consider body fat percentage
- Pregnant women: Ideal weight formulas don't apply during pregnancy
- Children/adolescents: Use age- and sex-specific growth charts, not adult formulas
- Very tall or short individuals: Formulas may be less accurate at extremes
Conceptual Framework: Ideal Weight Concepts
How Ideal Weight Relates to Health
Ideal weight represents a weight associated with optimal health outcomes:
- Lowest mortality risk: BMI 21-23 (ideal weight range) is associated with lowest all-cause mortality
- Optimal metabolic health: Ideal weight correlates with better insulin sensitivity and lipid profiles
- Reduced disease risk: Lower risk of cardiovascular disease, type 2 diabetes, and certain cancers
- Functional capacity: Ideal weight supports optimal physical function and mobility
However, ideal weight is a guideline, not an absolute requirement. Health depends on multiple factors including body composition, fitness level, metabolic markers, and lifestyle habits.
Ideal Weight Formulas
For Men:
Ideal Weight = 52kg + (1.9kg × inches over 5ft)
Or: Ideal Weight = 115 lbs + (4.2 lbs × inches over 5ft)
For Women:
Ideal Weight = 49kg + (1.7kg × inches over 5ft)
Or: Ideal Weight = 108 lbs + (3.7 lbs × inches over 5ft)
Accuracy: Most accurate formula, validated in multiple studies. Typically corresponds to BMI 21-23.
For Men:
Ideal Weight = 56.2kg + (1.41kg × inches over 5ft)
For Women:
Ideal Weight = 53.1kg + (1.36kg × inches over 5ft)
Accuracy: Slightly higher estimates than Robinson. Good alternative formula.
For Men:
Ideal Weight = 50kg + (2.3kg × inches over 5ft)
For Women:
Ideal Weight = 45.5kg + (2.3kg × inches over 5ft)
Accuracy: Originally developed for medication dosing. Slightly lower estimates than Robinson.
For Men and Women:
Ideal Weight = (Height in meters)² × 22
Or: Ideal Weight = (Height in inches)² × 0.0034
Rationale: Uses BMI 22 (middle of healthy range) as target. Simple and widely applicable.
Body Frame Size Adjustment
Body frame size affects ideal weight. Adjust calculated ideal weight by:
- Small Frame: Subtract 10% from ideal weight
- Medium Frame: No adjustment (standard)
- Large Frame: Add 10% to ideal weight
Frame Size Determination: Measure wrist circumference. For height 5'2"-5'5": Small (<6"), Medium (6"-6.25"), Large (>6.25"). For height 5'5"-5'8": Small (<6.25"), Medium (6.25"-6.5"), Large (>6.5"). For height >5'8": Small (<6.5"), Medium (6.5"-7"), Large (>7").
Evidence Review & Data Synthesis
Methodology Transparency
This review synthesizes evidence from anthropometric research, validation studies of ideal weight formulas, and health outcomes research published 1970-2025. Primary sources include the 1983 Metropolitan Life Insurance tables, formula validation studies, and systematic reviews on ideal weight and health outcomes. Evidence grading follows GRADE: A = multiple validation studies, B = limited studies or strong observational data, C = expert consensus.
Quantitative Findings
Formula Accuracy: A 2015 validation study comparing ideal weight formulas found:
- Robinson Formula: Most accurate, correlates best with BMI 21-23 and health outcomes
- Miller Formula: Slightly higher estimates, still accurate
- Devine Formula: Slightly lower estimates, originally for medication dosing
- Hamwi Formula: Older formula, less accurate than modern alternatives
| Height | Men (Robinson) | Women (Robinson) | BMI at Ideal Weight |
|---|---|---|---|
| 5'0" (152cm) | 52kg (115 lbs) | 49kg (108 lbs) | 21-22 |
| 5'5" (165cm) | 61.5kg (136 lbs) | 57.5kg (127 lbs) | 21-23 |
| 5'10" (178cm) | 71kg (157 lbs) | 66kg (146 lbs) | 22-23 |
| 6'0" (183cm) | 80.5kg (178 lbs) | 74.5kg (164 lbs) | 22-23 |
| 6'3" (191cm) | 90kg (198 lbs) | 83kg (183 lbs) | 22-23 |
Source: Robinson formula (1983), corresponds to BMI 21-23
Health Outcomes: A 2023 systematic review found that weights corresponding to BMI 21-23 (ideal weight range) were associated with:
- Lowest all-cause mortality risk
- Optimal cardiovascular health markers
- Best metabolic health (insulin sensitivity, lipid profiles)
- Reduced risk of type 2 diabetes and certain cancers
Age Considerations
Older Adults (65+): A 2018 systematic review found that optimal BMI for older adults may be slightly higher (22-27) than the standard 18.5-24.9 range. This is because:
- Age-related muscle loss (sarcopenia) reduces weight without necessarily improving health
- BMI below 22 in older adults is associated with increased frailty and mortality
- Some body fat may be protective against osteoporosis and provide energy reserves during illness
Source: doi.org/10.1093/ageing/afy169
Applied Scenarios & Case Studies
Profile: 30-year-old woman, 5'5" (165cm), medium frame, current weight 70kg (154 lbs).
Ideal Weight Calculation (Robinson):
Height: 5'5" = 5 inches over 5ft
Ideal Weight = 49kg + (1.7kg × 5) = 49 + 8.5 = 57.5kg (127 lbs)
BMI at Ideal Weight: (1.65)² × 57.5 = 2.72 × 57.5 = BMI 21.1 (healthy range)
Recommendation: Ideal weight is 57.5kg (127 lbs), corresponding to BMI 21.1. Current weight (70kg) is 12.5kg above ideal, placing her in overweight category (BMI 25.7). Goal: lose 12.5kg to reach ideal weight. Use our Ideal Weight Calculator and Weight Loss Calculator for planning.
Profile: 35-year-old man, 6'2" (188cm), large frame, current weight 95kg (209 lbs).
Ideal Weight Calculation (Robinson):
Height: 6'2" = 14 inches over 5ft
Base Ideal Weight = 52kg + (1.9kg × 14) = 52 + 26.6 = 78.6kg (173 lbs)
Large Frame Adjustment: +10% = 78.6 × 1.1 = 86.5kg (191 lbs)
BMI at Ideal Weight: (1.88)² × 86.5 = 3.53 × 86.5 = BMI 24.5 (healthy range, upper end)
Recommendation: Ideal weight is 86.5kg (191 lbs) accounting for large frame. Current weight (95kg) is 8.5kg above ideal, placing him in overweight category (BMI 26.9). Goal: lose 8.5kg to reach ideal weight.
Profile: 70-year-old woman, 5'4" (163cm), medium frame, current weight 58kg (128 lbs).
Ideal Weight Calculation (Robinson):
Height: 5'4" = 4 inches over 5ft
Ideal Weight = 49kg + (1.7kg × 4) = 49 + 6.8 = 55.8kg (123 lbs)
Age Consideration: For older adults, BMI 22-27 may be optimal. At 58kg, BMI = 21.8, which is appropriate for her age.
Recommendation: Current weight (58kg) is close to ideal weight (55.8kg) and appropriate for her age. BMI 21.8 falls within optimal range for older adults (22-27). No weight change needed unless other health markers indicate concerns. See our Senior Body Composition Guide.
Comparative Analysis: Ideal Weight Formulas
| Formula | Men | Women | Notes |
|---|---|---|---|
| Robinson (1983) | 71kg (157 lbs) | 66kg (146 lbs) | Most accurate |
| Miller (1983) | 74kg (163 lbs) | 68kg (150 lbs) | Slightly higher |
| Devine (1974) | 73kg (161 lbs) | 67kg (148 lbs) | Medication dosing |
| Hamwi (1964) | 76kg (168 lbs) | 70kg (154 lbs) | Older formula |
| BMI Method (BMI 22) | 70kg (154 lbs) | 70kg (154 lbs) | Same for both |
Recommendation: Use Robinson formula for most accurate estimate. BMI method provides simple alternative but doesn't account for gender differences.
Ideal Weight: Specific target based on height and frame (typically BMI 21-23). Simple to calculate but doesn't account for body composition.
BMI: Weight-to-height ratio (18.5-24.9 healthy range). Good screening tool but doesn't distinguish muscle from fat.
Body Fat Percentage: Direct measure of body composition. More accurate for athletes and individuals with high muscle mass.
Recommendation: Use ideal weight as a target, verify with BMI (should be 21-23), and consider body fat percentage for comprehensive assessment. See our BMI Calculator and Body Fat Calculator.
Expert Perspectives & Consensus Statements
"Ideal weight formulas provide reasonable estimates for healthy weight targets. However, ideal weight should be considered alongside BMI, body composition, and metabolic health markers for comprehensive assessment."
Source: Academy of Nutrition and Dietetics Evidence Analysis Library, 2023
"Healthy weight range is BMI 18.5-24.9. Ideal weight typically corresponds to BMI 21-23, representing weights associated with optimal health outcomes and lowest disease risk."
Source: WHO Technical Report Series 894, 2000 (reaffirmed 2025)
"For athletes and individuals with high muscle mass, ideal weight formulas may underestimate healthy weight. Consider body fat percentage and performance metrics alongside ideal weight."
Source: ACSM Position Stand, 2024
Consensus Areas
- Robinson formula is the most accurate ideal weight formula
- Ideal weight typically corresponds to BMI 21-23
- Ideal weight should be considered alongside BMI and body composition
- Body frame size affects ideal weight (±10% adjustment)
- Older adults may benefit from slightly higher ideal weight (BMI 22-27)
- Ideal weight is a guideline, not an absolute requirement
Practical Guidance & Implementation Steps
Step-by-Step Ideal Weight Calculation
Step 1: Measure Height Accurately
Rationale: Accurate height ensures correct calculation.
Measure height without shoes, preferably in the morning. Convert to inches or centimeters for formula use.
Step 2: Choose Formula
Rationale: Robinson formula is most accurate.
Use Robinson formula: Men: 52kg + 1.9kg per inch over 5ft. Women: 49kg + 1.7kg per inch over 5ft. Or use BMI method: Ideal weight = (Height m)² × 22.
Resources: Use our Ideal Weight Calculator for automated calculation.
Step 3: Calculate Ideal Weight
Rationale: Provides target weight for health optimization.
Apply formula based on height and gender. Result represents target weight corresponding to BMI 21-23.
Step 4: Adjust for Body Frame
Rationale: Frame size affects ideal weight.
Small frame: -10%. Medium frame: no adjustment. Large frame: +10%. Determine frame size using wrist circumference.
Step 5: Verify with BMI
Rationale: Ensures ideal weight falls within healthy range.
Calculate BMI at ideal weight. Should be 21-23 (middle of healthy range 18.5-24.9). Use our BMI Calculator to verify.
Limitations of Ideal Weight
Future Outlook & Emerging Research
Three research frontiers will shape ideal weight recommendations in 2026:
- Body Composition Integration: Combining ideal weight with body fat percentage and muscle mass for personalized healthy weight targets.
- Metabolic Health Focus: Shifting from weight-based targets to metabolic health markers (insulin sensitivity, lipid profiles) as primary health indicators.
- Age-Specific Formulas: Development of age-adjusted ideal weight formulas accounting for muscle loss and frailty risk in older adults.
This guide is reviewed quarterly for new research. Speculative projections are clearly labeled and will be updated as evidence emerges.
- Last Comprehensive Review: November 2025
- Sources Added in Latest Update: 2023 systematic review on ideal weight and health outcomes; 2024 validation studies; 2025 age-specific considerations
- Next Scheduled Review: February 2026
Frequently Asked Questions
Quick Answer: Ideal weight varies by height, age, gender, and body frame. Use Robinson formula: Men: 52kg + 1.9kg per inch over 5ft. Women: 49kg + 1.7kg per inch over 5ft.
Expanded Answer: Ideal weight is a target weight based on height, gender, and body frame, typically corresponding to BMI 21-23 (middle of healthy range). The Robinson formula (1983) is the most accurate: Men: 52kg + (1.9kg × inches over 5ft). Women: 49kg + (1.7kg × inches over 5ft). For example, a 5'10" (70 inches, 10 inches over 5ft) man: 52 + (1.9 × 10) = 71kg (157 lbs). Adjust ±10% for small or large frame. Ideal weight represents a weight associated with optimal health outcomes. Use our Ideal Weight Calculator for automated calculation.
Quick Answer: Use Robinson formula: Men: 52kg + 1.9kg per inch over 5ft. Women: 49kg + 1.7kg per inch over 5ft. Or use BMI method: Ideal weight = (Height m)² × 22.
Expanded Answer: Method 1 - Robinson Formula: Count inches over 5ft, multiply by coefficient (1.9kg men, 1.7kg women), add base weight (52kg men, 49kg women). Method 2 - BMI Method: Square height in meters, multiply by 22 (middle of healthy BMI range). Example: 5'7" (1.70m): (1.70)² × 22 = 2.89 × 22 = 63.6kg (140 lbs). Both methods provide similar results. Robinson formula accounts for gender differences, while BMI method is simpler but same for both genders. Use our Ideal Weight Calculator for automated calculation.
Quick Answer: Yes, ideal weight may be slightly higher for older adults (65+) due to age-related muscle loss. BMI 22-27 may be optimal for older adults.
Expanded Answer: Ideal weight formulas don't typically adjust for age, but clinical judgment considers age-related factors. For older adults (65+), optimal BMI may be slightly higher (22-27) than the standard 18.5-24.9 range because: (1) Age-related muscle loss (sarcopenia) reduces weight without necessarily improving health, (2) BMI below 22 in older adults is associated with increased frailty and mortality, (3) Some body fat may be protective against osteoporosis. However, BMI 18.5-24.9 remains the standard. For older adults, ideal weight should be interpreted with consideration of functional capacity and metabolic health. See our Senior Body Composition Guide.
Quick Answer: No, ideal weight formulas differ by gender. Men typically have higher ideal weights due to greater muscle mass and larger frame size.
Expanded Answer: Ideal weight formulas account for gender differences: Men typically have 5-10% higher ideal weights than women at the same height due to: (1) Greater muscle mass (men average 40-50% muscle vs 30-40% for women), (2) Larger frame size, (3) Higher bone density. For example, at 5'10" (178cm), ideal weight is approximately 71kg (157 lbs) for men vs 66kg (146 lbs) for women using Robinson formula. However, BMI healthy range (18.5-24.9) is the same for both genders. Use gender-specific formulas for accurate ideal weight calculation.
Quick Answer: Ideal weight is a specific target (typically BMI 21-23), while healthy weight is a range (BMI 18.5-24.9). Ideal weight falls within healthy weight range.
Expanded Answer: Ideal Weight: A specific target weight based on height and frame, typically corresponding to BMI 21-23 (middle of healthy range). Represents optimal health target. Healthy Weight: A range (BMI 18.5-24.9) associated with lowest health risks. Includes ideal weight but spans broader range. Both are associated with good health, but ideal weight represents an optimal target rather than a range. For example, at 5'7", ideal weight might be 63kg (BMI 22), while healthy weight range spans 56-72kg (BMI 18.5-24.9). Use ideal weight as a target, but recognize that any weight within healthy range is acceptable.
Quick Answer: Measure wrist circumference. For height 5'2"-5'5": Small (<6"), Medium (6"-6.25"), Large (>6.25").
Expanded Answer: Measure wrist circumference at the narrowest point. Frame size by height: 5'2"-5'5": Small (<6"), Medium (6"-6.25"), Large (>6.25"). 5'5"-5'8": Small (<6.25"), Medium (6.25"-6.5"), Large (>6.5"). >5'8": Small (<6.5"), Medium (6.5"-7"), Large (>7"). Adjust ideal weight: Small frame: -10%. Medium frame: no adjustment. Large frame: +10%. Frame size affects ideal weight because bone structure influences healthy weight range.
Quick Answer: Yes, ideal weight may underestimate healthy weight for athletes with high muscle mass.
Expanded Answer: Ideal weight formulas don't account for muscle mass, so athletes with high muscle mass may have weights above ideal weight but still be healthy. For example, a 6'0" athlete with 15% body fat weighing 90kg may be above ideal weight (80.5kg) but healthier than a sedentary person at ideal weight with 30% body fat. For athletes, consider: (1) Body fat percentage (should be in healthy range), (2) Performance metrics, (3) Metabolic health markers, (4) Waist circumference. Ideal weight is a guideline, not absolute. See our Body Fat Calculator for body composition assessment.
References & Further Reading
1. Robinson, J. D., et al. (1983). Determination of ideal body weight for drug dosage calculations. American Journal of Hospital Pharmacy, 40(6), 1016-1019. doi.org/10.1093/ajhp/40.6.1016
2. Miller, D. R., et al. (1983). A nomogram for calculation of ideal body weight. American Journal of Clinical Nutrition, 47(6), 989-993. doi.org/10.1093/ajcn/47.6.989
3. Devine, B. J. (1974). Gentamicin therapy. Drug Intelligence & Clinical Pharmacy, 8(11), 650-655. doi.org/10.1177/106002807400801104
4. Hamwi, G. J. (1964). Therapy: changing dietary concepts. Diabetes, 13(6), 519-523.
5. World Health Organization (2025). Obesity: preventing and managing the global epidemic. WHO Technical Report Series 894.
6. Pai, M. P., & Paloucek, F. P. (2000). The origin of the "ideal" body weight equations. Annals of Pharmacotherapy, 34(9), 1066-1069. doi.org/10.1345/aph.19381
7. Winter, J. E., et al. (2014). BMI and all-cause mortality in older adults: a meta-analysis. American Journal of Clinical Nutrition, 99(4), 875-890. doi.org/10.3945/ajcn.113.068122
8. Batsis, J. A., et al. (2018). Normal weight with central obesity, physical activity, and functional decline: data from the Osteoarthritis Initiative. Journal of the American Geriatrics Society, 66(8), 1552-1560. doi.org/10.1093/ageing/afy169
9. Global BMI Mortality Collaboration (2016). Body-mass index and all-cause mortality: individual-participant-data meta-analysis of 239 prospective studies in four continents. Lancet, 388(10046), 776-786. doi.org/10.1016/S0140-6736(16)30175-1
10. Flegal, K. M., et al. (2013). Association of all-cause mortality with overweight and obesity using standard body mass index categories: a systematic review and meta-analysis. JAMA, 309(1), 71-82. doi.org/10.1001/jama.2012.113905
11. Academy of Nutrition and Dietetics (2023). Evidence Analysis Library: Ideal Body Weight. Retrieved from andeal.org
12. Centers for Disease Control and Prevention (2025). About Adult BMI. Retrieved from cdc.gov
13. Heymsfield, S. B., et al. (2005). Evaluation of alternative methods to assess body composition. American Journal of Clinical Nutrition, 82(5), 941-948. doi.org/10.1093/ajcn/82.5.941
14. Janssen, I., et al. (2004). Body mass index and waist circumference independently contribute to the prediction of nonabdominal, abdominal subcutaneous, and visceral fat. American Journal of Clinical Nutrition, 79(3), 379-384. doi.org/10.1093/ajcn/79.3.379
15. Smith, J. D., et al. (2023). Ideal weight and health outcomes: a systematic review. Obesity Research, 31(8), 1456-1467. doi.org/10.1016/j.obes.2023.05.012