Ideal Weight Calculator - Find Your Healthy Weight

Calculate your ideal body weight for free using multiple scientifically validated formulas. Your ideal weight depends on factors like height, gender, age, body frame, and muscle mass. Understanding your healthy weight range is essential for setting realistic fitness goals and maintaining optimal health.

What is Ideal Body Weight?

Ideal body weight (IBW) is an estimate of the weight range that correlates with optimal health and longevity for your specific characteristics. Unlike a single “perfect” number, your ideal weight is actually a range that considers your unique body composition and health status.

Scientific Formulas for Ideal Weight

Different formulas have been developed over decades of medical research. Our calculator uses the most recognized methods to give you a comprehensive view of your healthy weight range.

Robinson Formula (1983)

One of the most widely used formulas, developed by J.D. Robinson for clinical nutrition.

For Men:

• IBW = 52 kg + 1.9 kg per inch over 5 feet

For Women:

• IBW = 49 kg + 1.7 kg per inch over 5 feet

Example: A 5’9” (69 inches) man

• 69 inches - 60 inches = 9 inches over 5 feet
• 52 + (1.9 × 9) = 52 + 17.1 = 69.1 kg (152 lbs)

Miller Formula (1983)

Developed alongside Robinson’s formula, provides similar but slightly different estimates.

For Men:

• IBW = 56.2 kg + 1.41 kg per inch over 5 feet

For Women:

• IBW = 53.1 kg + 1.36 kg per inch over 5 feet

Characteristics: Tends to suggest slightly higher weights than Robinson formula, especially for taller individuals.

Devine Formula (1974)

Originally created to calculate medication dosages, widely adopted for ideal weight estimation.

For Men:

• IBW = 50 kg + 2.3 kg per inch over 5 feet

For Women:

• IBW = 45.5 kg + 2.3 kg per inch over 5 feet

Note: This formula tends to suggest lower weights for women and is commonly used in medical settings.

Hamwi Formula (1964)

One of the oldest and simplest formulas, developed by Dr. G.J. Hamwi.

For Men:

• IBW = 48 kg + 2.7 kg per inch over 5 feet

For Women:

• IBW = 45.5 kg + 2.2 kg per inch over 5 feet

Usage: Commonly used in clinical nutrition and dietetics for quick estimates.

Body Frame Adjustment

Most formulas provide a base estimate that should be adjusted for body frame size:

• Small frame: Subtract 10% from calculated IBW
• Medium frame: Use calculated IBW as is
• Large frame: Add 10% to calculated IBW

Example: If your calculated IBW is 70 kg with a large frame:

• Adjusted IBW = 70 + (70 × 0.10) = 77 kg

BMI-Based Healthy Weight Ranges

Another approach uses Body Mass Index to determine healthy weight ranges. The World Health Organization defines healthy BMI as 18.5-24.9.

Healthy Weight by Height

Height	Healthy Weight Range (BMI 18.5-24.9)
4’10” (147 cm)	91-119 lbs (41-54 kg)
5’0” (152 cm)	97-127 lbs (44-58 kg)
5’2” (157 cm)	104-136 lbs (47-62 kg)
5’4” (163 cm)	110-144 lbs (50-65 kg)
5’6” (168 cm)	118-154 lbs (54-70 kg)
5’8” (173 cm)	125-164 lbs (57-74 kg)
5’10” (178 cm)	132-174 lbs (60-79 kg)
6’0” (183 cm)	140-184 lbs (64-83 kg)
6’2” (188 cm)	148-194 lbs (67-88 kg)
6’4” (193 cm)	156-205 lbs (71-93 kg)

Note: These ranges apply to adults aged 20 and older with medium body frames.

Factors Affecting Your Ideal Weight

Your ideal weight isn’t determined by height alone. Multiple factors influence what’s healthy for your unique body.

1. Height

The most obvious factor - taller individuals naturally weigh more. All standard formulas use height as the primary variable.

2. Gender

Men typically have:

• 10-15% more muscle mass
• Lower essential body fat requirements (2-5% vs 10-13%)
• Higher bone density
• Greater lean mass

Women naturally have:

• Higher essential fat for reproductive health
• Smaller bone structure on average
• Different fat distribution patterns
• Hormonal considerations affecting weight

3. Age

20-30 years: Peak metabolic rate and muscle mass

• Ideal weight formulas apply most directly

30-50 years: Gradual muscle loss begins (sarcopenia)

• Metabolism decreases 2-5% per decade
• Acceptable range may shift slightly upward

50+ years: Increased age-related muscle loss

• Higher acceptable body fat percentages
• Focus shifts to maintaining functional strength
• BMI 23-27 may be ideal for longevity in this age group

Research findings: Studies show that slightly higher BMI (25-27) in older adults correlates with better health outcomes and longevity compared to BMI 18.5-22.

4. Body Frame Size

Frame size significantly impacts ideal weight but is often overlooked.

How to Determine Your Body Frame

Wrist Circumference Method:

For Men:

• Small frame: Wrist < 6.5 inches (< 16.5 cm)
• Medium frame: Wrist 6.5-7.5 inches (16.5-19 cm)
• Large frame: Wrist > 7.5 inches (> 19 cm)

For Women:

• Small frame: Wrist < 6 inches (< 15.2 cm)
• Medium frame: Wrist 6-6.5 inches (15.2-16.5 cm)
• Large frame: Wrist > 6.5 inches (> 16.5 cm)

Elbow Breadth Method:

Extend your arm forward at 90°, fingers pointing up. Measure the distance between the two prominent bones on either side of your elbow.

For Men (height-adjusted):

Height 5’2”-5’3”: Small <2.5”, Medium 2.5-2.875”, Large >2.875” Height 5’4”-5’7”: Small <2.625”, Medium 2.625-2.875”, Large >2.875” Height 5’8”-5’11”: Small <2.625”, Medium 2.625-3”, Large >3” Height 6’0”-6’3”: Small <2.75”, Medium 2.75-3.125”, Large >3.125” Height >6’4”: Small <2.875”, Medium 2.875-3.25”, Large >3.25”

For Women (height-adjusted):

Height 4’10”-5’1”: Small <2.25”, Medium 2.25-2.5”, Large >2.5” Height 5’2”-5’5”: Small <2.25”, Medium 2.25-2.625”, Large >2.625” Height 5’6”-5’9”: Small <2.375”, Medium 2.375-2.625”, Large >2.625” Height 5’10”+: Small <2.375”, Medium 2.375-2.75”, Large >2.75”

5. Muscle Mass and Athletic Build

Critical consideration: Standard formulas don’t account for muscle mass.

Athletes and bodybuilders:

• May exceed “ideal weight” by 20-40 pounds
• BMI often classifies them as “overweight”
• Low body fat percentage (10-15% men, 15-22% women)
• Superior health markers despite higher weight

Better indicators for athletic individuals:

• Body fat percentage (Navy Method, DEXA scan)
• Waist-to-hip ratio
• Waist circumference
• Body composition analysis

Example: A 5’10” athletic male with 180 lbs and 12% body fat is healthier than a sedentary male at 160 lbs with 25% body fat, even though the second is closer to “ideal weight.”

6. Bone Density

Factors affecting bone mass:

• Genetics (up to 80% determined by heredity)
• Ethnicity (African Americans typically have 10% greater bone density)
• Gender (men have denser bones)
• Physical activity (weight-bearing exercise increases density)

Weight impact: Individuals with higher bone density will naturally weigh more while maintaining optimal health.

7. Ethnicity and Genetics

Research shows different healthy weight ranges for various populations:

Asian populations:

• Higher health risks at lower BMIs
• WHO recommends lower cutoffs (overweight at BMI 23, obese at 27.5)
• Greater visceral fat accumulation at same BMI

African and African-American populations:

• Higher muscle mass and bone density
• Lower body fat at same BMI
• May have healthy weight slightly above standard formulas

Hispanic/Latino populations:

• Higher risk of type 2 diabetes at lower BMIs
• Important to consider waist circumference
• Individual variation based on indigenous vs. European heritage

Why Ideal Weight Varies by Formula

You may notice different formulas give different results - this is normal and expected.

Historical Context

Each formula was developed for specific purposes:

• Hamwi (1964): Quick clinical estimates
• Devine (1974): Medication dosing calculations
• Robinson & Miller (1983): Nutrition assessment
• Modern BMI ranges: Population health screening

Statistical Differences

For a 5’9” (175 cm) man:

• Hamwi: 79 kg (174 lbs)
• Devine: 75 kg (166 lbs)
• Robinson: 72 kg (159 lbs)
• Miller: 72 kg (160 lbs)
• BMI range (18.5-24.9): 58-74 kg (128-164 lbs)

Variation: Up to 21 kg (46 lbs) difference between methods!

What This Means for You

1. Don’t obsess over a single number - Focus on the range
2. Consider your body frame - Adjust accordingly
3. Evaluate your body composition - Muscle vs. fat matters more
4. Monitor health markers - Blood pressure, cholesterol, energy levels
5. Feel good in your body - Sustainable weight you can maintain

How to Reach Your Ideal Weight Safely

Achieving your ideal weight should be gradual and sustainable, not a crash diet.

1. Set Realistic Goals

Safe weight loss rate:

• Overweight: 1-2 lbs (0.5-1 kg) per week
• Obese: 1-2.5 lbs (0.5-1.2 kg) per week
• Slightly overweight: 0.5-1 lb (0.25-0.5 kg) per week

Timeline calculator:

• Current weight: 200 lbs
• Target weight: 165 lbs
• Deficit: 35 lbs
• At 1.5 lbs/week: 23 weeks (~6 months)

2. Create a Moderate Caloric Deficit

Step 1: Calculate your TDEE (Total Daily Energy Expenditure)

• Use our TDEE Calculator
• Accounts for activity level and metabolism

Step 2: Create a 15-25% deficit

• Example TDEE: 2,400 calories
• 20% deficit: 2,400 - 480 = 1,920 calories/day
• Expected loss: ~1.5 lbs/week

Avoid extreme deficits:

• 30% deficit leads to muscle loss

• Slows metabolism (adaptive thermogenesis)
• Increases hunger and risk of binge eating
• Difficult to sustain long-term

3. Prioritize Protein Intake

Benefits:

• Preserves muscle during weight loss
• Highest satiety of all macronutrients
• Higher thermic effect (burns more calories to digest)
• Supports recovery and repair

Recommended intake:

• Weight loss: 0.8-1 g per lb body weight
• Maintenance: 0.7-0.8 g per lb body weight
• Muscle building: 1-1.2 g per lb body weight

Example for 180 lb person:

• Target: 144-180 g protein daily
• Spread across 4-5 meals
• ~30-40 g per meal

4. Implement Strength Training

Why it’s essential:

• Preserves muscle mass during caloric deficit
• Increases resting metabolic rate
• Improves insulin sensitivity
• Shapes body composition
• Strengthens bones

Recommended program:

• 3-5 sessions per week
• Full-body or split routine
• Progressive overload (gradually increase weight/reps)
• Compound exercises (squats, deadlifts, bench press, rows)

5. Add Strategic Cardio

Types:

LISS (Low-Intensity Steady State):

• 30-60 minutes
• Heart rate 60-70% max
• Examples: Walking, cycling, swimming
• Benefits: Fat burning, active recovery, stress relief

HIIT (High-Intensity Interval Training):

• 15-30 minutes
• Intervals of max effort + recovery
• Examples: Sprints, cycling intervals, rowing
• Benefits: Time-efficient, increases metabolism for hours post-workout

Recommendation: 2-3 LISS sessions + 1-2 HIIT sessions weekly

6. Track Your Progress

Weigh yourself:

• Same time daily (morning, after bathroom, before eating)
• Take weekly average (reduces daily fluctuation noise)
• Expect 2-4 lb daily variation from water, food, hormones

Body measurements:

• Waist, hips, chest, arms, thighs
• Every 2-4 weeks
• More accurate than scale for body composition changes

Progress photos:

• Same location, lighting, time
• Front, side, back views
• Every 2-4 weeks
• Visual changes often appear before scale changes

Health markers:

• Energy levels
• Sleep quality
• Mood and mental clarity
• Physical performance
• Hunger and satiety

7. Build Sustainable Habits

Avoid:

• ❌ Eliminating entire food groups
• ❌ “Good” vs. “bad” food mentality
• ❌ Extreme restrictions
• ❌ Relying on supplements or pills
• ❌ Following celebrity fad diets

Embrace:

• ✅ 80/20 rule (80% nutrient-dense, 20% flexible)
• ✅ Meal planning and prep
• ✅ Mindful eating practices
• ✅ Adequate sleep (7-9 hours)
• ✅ Stress management
• ✅ Social support and accountability

Common Misconceptions About Ideal Weight

Myth 1: “There’s One Perfect Weight for Everyone of My Height”

Truth: Ideal weight is a range, not a single number. Two people of the same height can have different healthy weights based on frame size, muscle mass, genetics, and age.

Myth 2: “BMI is Completely Useless”

Truth: BMI has limitations (doesn’t distinguish muscle from fat) but is a useful screening tool for population health. It works well for most sedentary individuals but fails for athletes and muscular individuals.

Myth 3: “Ideal Weight Means Six-Pack Abs”

Truth: Six-pack abs require very low body fat (6-12% men, 14-20% women), which isn’t necessary for optimal health. Many healthy individuals have 15-20% (men) or 22-30% (women) body fat.

Myth 4: “If I’m Outside the Ideal Range, I’m Unhealthy”

Truth: Weight is just one health indicator. Blood pressure, cholesterol, blood sugar, fitness level, and overall well-being matter more. Some people are healthy slightly outside standard ranges.

Myth 5: “Ideal Weight Never Changes”

Truth: Your ideal weight can shift with age, activity level, and life circumstances. What’s healthy at 25 may differ from age 55. Pregnancy, menopause, and aging naturally affect body composition.

Myth 6: “I Should Weigh What I Did in High School”

Truth: Adult bodies are different. Expecting to maintain high school weight ignores natural physiological changes, muscle development, and hormonal shifts. Focus on current health, not past numbers.

Myth 7: “Muscle and Fat Weigh the Same”

Truth: Muscle is denser than fat. 5 lbs of muscle takes up ~20% less space than 5 lbs of fat. You can weigh the same but look leaner with more muscle mass.

Health Risks of Being Underweight

While obesity gets more attention, being underweight (BMI <18.5) carries serious health risks:

Nutritional Deficiencies

• Iron deficiency → Anemia
• Calcium/Vitamin D deficiency → Osteoporosis
• Protein deficiency → Muscle wasting
• Vitamin B12 deficiency → Neurological problems

Weakened Immune System

• Increased susceptibility to infections
• Longer recovery times
• Higher risk of complications from illness

Hormonal Imbalances

• Women: Irregular periods, amenorrhea, infertility
• Men: Low testosterone, reduced sperm count
• Both: Thyroid dysfunction, stress hormone dysregulation

Bone Health

• Reduced bone density
• Increased fracture risk
• Higher osteoporosis risk in later life

Mental Health

• Increased risk of depression and anxiety
• Cognitive impairment
• Reduced concentration and memory

Reduced Muscle Mass

• Weakness and fatigue
• Poor physical performance
• Loss of functional independence in older adults

If you’re underweight:

1. Consult a healthcare provider to rule out underlying conditions
2. Work with a registered dietitian for a weight gain plan
3. Focus on nutrient-dense, calorie-rich foods
4. Incorporate strength training to build muscle
5. Address any psychological barriers to eating

Health Risks of Being Overweight

Carrying excess weight, especially body fat, increases risk for numerous chronic conditions:

Cardiovascular Disease

• High blood pressure (hypertension)
• High cholesterol and triglycerides
• Atherosclerosis (plaque buildup in arteries)
• Heart attack and stroke
• Heart failure

Metabolic Disorders

• Type 2 diabetes
• Insulin resistance and prediabetes
• Metabolic syndrome
• Non-alcoholic fatty liver disease

Cancer Risk

Excess weight increases risk for:

• Breast (postmenopausal)
• Colon and rectum
• Endometrial
• Kidney
• Esophageal
• Pancreatic
• Gallbladder

Respiratory Issues

• Sleep apnea
• Asthma
• Obesity hypoventilation syndrome
• Reduced lung function

Joint and Bone Problems

• Osteoarthritis (especially knees, hips, spine)
• Gout
• Back pain
• Reduced mobility

Reproductive Health

• Women: Polycystic ovary syndrome (PCOS), irregular periods, infertility
• Men: Erectile dysfunction, low testosterone
• Pregnancy complications

Mental Health

• Depression and anxiety
• Low self-esteem
• Body image issues
• Social stigma and discrimination

Good news: Losing just 5-10% of body weight can significantly improve health markers, even if you remain above “ideal weight.”

Frequently Asked Questions

What’s the most accurate formula for ideal weight?

No single formula is “most accurate” because ideal weight varies by individual factors. The Robinson and Miller formulas are most commonly used in modern clinical practice. The best approach is to:

1. Calculate your range using multiple formulas
2. Adjust for body frame size
3. Consider your muscle mass and activity level
4. Focus on body composition, not just weight

How do I know if I have a small, medium, or large frame?

Two reliable methods:

1. Wrist circumference: Measure your wrist at the narrowest point (just below the wrist bone)
2. Elbow breadth: Extend arm forward at 90°, measure distance between elbow bones

See the detailed measurements in the “Body Frame Size” section above. If measurements conflict, use the wrist method as it’s simpler and less prone to error.

Can I be healthy outside my ideal weight range?

Yes, absolutely. Ideal weight formulas are guidelines, not absolute rules. You can be healthy with:

• Higher muscle mass (athletes, active individuals)
• Large bone structure
• Slightly higher weight in older adults (research shows BMI 25-27 may be optimal for longevity after age 65)

Key indicators of health regardless of weight:

• Normal blood pressure (<120/80)
• Healthy cholesterol levels
• Normal blood sugar
• Good cardiovascular fitness
• Adequate muscle mass and strength
• Healthy waist circumference (<40” men, <35” women)

Does ideal weight change with age?

Yes. As you age:

Ages 20-30: Standard formulas apply most directly Ages 30-50: Gradual muscle loss begins, metabolism slows 2-5% per decade Ages 50+: Research suggests slightly higher BMI (23-27) may be optimal for longevity

Why the shift?

• Muscle mass decreases with age (sarcopenia)
• Bone density changes
• Hormonal changes (menopause, testosterone decline)
• Some weight provides reserves during illness recovery
• Very low BMI in older adults associated with frailty

Focus shifts from “ideal weight” to maintaining:

• Functional strength and mobility
• Healthy body composition
• Independence in daily activities
• Quality of life

How long does it take to reach ideal weight?

Depends on starting point and approach:

Safe rates:

• 1-2 lbs (0.5-1 kg) per week for most people
• 0.5-1 lb (0.25-0.5 kg) per week if close to goal
• Slower is often better for muscle preservation and sustainability

Example timelines:

20 lbs to lose: 10-20 weeks (2.5-5 months) 40 lbs to lose: 20-40 weeks (5-10 months) 60 lbs to lose: 30-60 weeks (7.5-15 months)

Important: Faster isn’t better. Rapid weight loss often means:

• Muscle loss along with fat
• Metabolic adaptation (slower metabolism)
• Higher likelihood of regain
• Nutritional deficiencies

Should I use ideal weight or BMI?

Use both as complementary tools:

Ideal weight formulas:

• More personalized (gender-specific)
• Quick estimate for target weight
• Don’t account for muscle mass

BMI:

• Population screening tool
• Provides a healthy range, not single number
• Doesn’t distinguish muscle from fat
• Less accurate for athletes, very tall/short individuals

Better approach:

1. Calculate both ideal weight range and healthy BMI range
2. Add body fat percentage measurement
3. Consider waist circumference (<40” men, <35” women)
4. Monitor how you feel, perform, and your health markers
5. Choose a sustainable weight you can maintain

Is it better to be slightly underweight or overweight?

Research shows moderate overweight may be safer than underweight:

Being slightly overweight (BMI 25-27):

• Some studies show lower mortality risk than BMI 18.5-22, especially in older adults
• Provides reserves during illness
• May indicate adequate nutrition and muscle mass

Being underweight (BMI <18.5):

• Associated with higher mortality risk
• Nutritional deficiencies
• Hormonal problems
• Weakened immune system
• Osteoporosis risk

Caveat: This doesn’t mean obesity is healthy. BMI >30 clearly increases health risks. The “sweet spot” appears to be BMI 20-27, with emphasis on:

• Good body composition (muscle vs. fat)
• Healthy waist circumference
• Active lifestyle
• Adequate nutrition

Bottom line: Focus on health markers and body composition, not achieving the lowest possible weight.

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Disclaimer: This calculator provides estimates based on scientifically validated formulas. Ideal weight varies significantly based on individual factors including muscle mass, bone density, body frame, and overall health. Always consult with a healthcare professional or registered dietitian for personalized weight management advice and before starting any diet or exercise program.