Is there really an ideal weight?

Clinically, there is no single 'perfect' weight, but rather a healthy weight range. Formulas provide useful clinical targets, but your true ideal weight depends on how you feel, your cardiovascular health, and your unique body composition.

What is the Devine formula and how is it calculated?

The Devine formula (1974) is the clinical standard for estimating ideal body weight, originally created for drug dosing. It starts from a base weight at 5 feet (60 inches) of height and adds a fixed amount for every inch above that: men = 50 kg + 2.3 kg per inch over 5 ft, and women = 45.5 kg + 2.3 kg per inch over 5 ft. For example, a 5 ft 10 in (178 cm) man = 50 + (10 × 2.3) = 73 kg. The calculator above runs the Devine formula for you and averages it with the Robinson, Miller and Hamwi formulas for a more balanced target.

Why do the formulas give different results?

The Devine and Hamwi formulas are classic clinical models from the 1960s–70s used for drug dosing. Robinson and Miller are independently derived formulas published in 1983 — each developed from its own dataset, not adapted from Devine or Hamwi — that produce slightly different targets due to different base weights and per-inch increments. Using the average of all four provides the most balanced result.

Does frame size really matter?

Yes, bone density heavily influences scale weight. Someone with a large frame naturally carries more skeletal mass and requires a higher ideal weight baseline (typically +10%) compared to someone with a small frame (-10%).

Should I aim for the lower or upper end of the range?

If you carry significant muscle mass, you should aim for the upper end (or even above it). It is highly recommended to pair your weight targets with an accurate reading from the Body Fat % Calculator.

Weight Science

Ideal Weight Calculator — Free

Discover your ideal weight range based on your height, age, and body composition using four scientifically validated clinical formulas including Devine, Robinson, Miller, and Hamwi.

Peer-Reviewed Formulas

Clinically Referenced

No Data Stored

Free Forever

Find Your Ideal Weight

Gender

Age (years)

Age adjusts the healthy BMI reference range for adults 65+ (senior guidelines use BMI 23–28).

Height

Height Unit

cmft·in

Enter your height in centimeters (e.g., 170 cm)

Valid range: 152–214 cm (approx. 5 ft – 7 ft)

Body Frame Size

The ±10% frame adjustment is applied to all four formulas. Clinical medication dosing uses the unadjusted medium-frame value.

Optional: Auto-calculate via wrist size (cm)

Men: Small <16.5 cm · Medium 16.5–19.1 cm · Large >19.1 cm
Valid range: 10–30 cm

Primary Formula Focus

Displays the average across all four major clinical formulas for a balanced target.

*This calculator is for informational purposes only. Please consult a healthcare professional before making any health decisions. See our medical disclaimer for more information.

Calculations are powered by the Devine, Robinson, Miller & Hamwi IBW Equations, four peer-reviewed clinical formulas for ideal body weight validated for adult assessment (Pai & Paloucek, Ann Pharmacother, 2000).

What Is the Ideal Weight for My Height?

Ideal weight varies by height, sex and the formula used. For a 5 ft 10 in (178 cm) man, clinical estimates range from 70.4–75.5 kg (155–166 lb) across the four main formulas — Devine, Robinson, Miller and Hamwi — at a medium frame. For women at the same height, the range is 66.1–68.7 kg (146–151 lb). This calculator averages all four for a balanced result.

What is Ideal Body Weight and How Is It Calculated?

Ideal Body Weight (IBW) is a clinical estimate of the optimal mass at which an individual is expected to function with the lowest risk of weight-related disease. Unlike BMI, IBW formulas account for height as the primary driver and use gender as a binary biological variable.

This calculator provides averages from the four most widely cited clinical formulas:

Formula	Year	Male Base (at 5 ft / 60 in)	Male Per Inch	Female Base (at 5 ft / 60 in)	Female Per Inch
Devine Formula	1974	50 kg	2.3 kg	45.5 kg	2.3 kg
Robinson Formula	1983	52 kg	1.9 kg	49 kg	1.7 kg
Miller Formula	1983	56.2 kg	1.41 kg	53.1 kg	1.36 kg
Hamwi Formula	1964	48.08 kg	2.722 kg	45.36 kg	2.268 kg

Source: A review of equations to estimate ideal body weight — NCBI / PubMed

Different Methods for Calculating Ideal Weight

Our calculator uses four distinct, scientifically validated formulas to provide a comprehensive view of your target weight range:

Devine Formula (1974)

The clinical gold standard. Originally developed to calculate the clearance of certain drugs in obese patients, it remains widely used in hospitals today for medication dosing due to its reliability. The Devine formula calculator works from a base of 50 kg (men) or 45.5 kg (women) at 5 ft, adding 2.3 kg per inch of height above that.

Robinson Formula (1983)

An independently derived formula published in the same year as Miller. Robinson uses a higher base weight for women (49 kg vs 45.5 kg in Devine) but a shallower per-inch increment for men, producing more conservative targets at taller heights — typically 2–4 kg below Devine for men above 170 cm.

Miller Formula (1983)

An independently derived formula from 1983 with the shallowest per-inch increment of the four. Miller tends to give the most conservative (lowest) ideal weights for taller individuals, while being the highest of the four for shorter statures — making it a useful lower-bound reference at average and above-average heights.

Hamwi Formula (1964)

The traditional standard used in dietetics and nutritional assessment. It provides a quick rule-of-thumb for dietitians to estimate a patient's baseline caloric needs and serves as an excellent comparative metric.

Factors That Influence Ideal Weight

Two individuals of the exact same height can have vastly different healthy weights. Several physiological factors dictate where your body naturally settles:

Height & Frame Size

Height is the primary variable in all weight formulas. However, bone density (frame size) also plays a massive role. Individuals with larger, denser skeletal structures naturally carry more weight and require a higher baseline target.

Muscle Mass

Muscle tissue is significantly denser than fat tissue. Athletes or individuals who engage in regular resistance training will naturally weigh more than sedentary individuals of the same size, even with lower body fat percentages.

Age

As we age, our metabolism naturally changes and body composition shifts. Older adults often experience a decrease in muscle mass (sarcopenia). A healthy weight target at age 20 may not be realistic or optimal at age 65.

Genetics

Genetic factors heavily influence your natural fat distribution and basal metabolic rate. Embracing natural variation is crucial; formulas provide averages, but genetics dictate your specific physiological reality.

Healthy Weight Range Calculator for Short Frames and Varying Demographics

Standard weight calculations frequently fail individuals on the shorter end of the height spectrum. Because traditional formulas operate on a linear scale, they can produce disproportionately low, occasionally unhealthy weight targets for women under 5'2" and men under 5'5".

A healthy weight range for shorter frames must account for the fact that vital organs, bone density, and essential fat require a minimum baseline of mass regardless of height. Adjusted calculators provide a more generous, realistic range, preventing the pursuit of biologically unsustainable low body weights that compromise metabolic health.

Ideal Weight Calculator Based on Real-World Frame Size and Age Variables

Skeletal structure plays an immense role in determining healthy weight parameters. A person with a large skeletal frame (indicated by broader shoulders, wider hips, and thicker wrists) will naturally require a higher weight classification than someone of the exact same height with a slight build.

Furthermore, chronological age alters body composition. As humans age, minor increases in body fat percentage and slight shifts in the BMI curve are considered protective against mortality, osteoporosis, and frailty. An accurate ideal weight calculation factors in both structural frame capacity and age-appropriate metabolic adaptations.

Ideal Weight Calculator for Endomorphs, Mesomorphs and Ectomorphs

The concept of somatotypes—ectomorph (lean, long limbs), mesomorph (muscular, athletic build), and endomorph (stockier, higher fat storage tendency)—provides a useful framework for understanding why standard formulas fall short for many individuals.

While modern science views these categories as a spectrum rather than strict genetic destinies, acknowledging your natural body type helps contextualize the calculator's results. An ectomorph might naturally sit at the absolute bottom of their ideal weight range effortlessly, whereas a mesomorph might constantly measure "overweight" by standard metrics while maintaining single-digit body fat.

Ideal Body Weight Calculator for Natural Bodybuilding Limits

For strength athletes and natural bodybuilders, the concept of an "ideal weight" shifts from general health metrics to physiological maximums. Determining how much lean muscle tissue a human frame can naturally support before reaching genetic limits is a critical step in setting realistic hypertrophy goals.

While standard clinical formulas estimate a healthy baseline, natural bodybuilders often refer to their Fat-Free Mass Index (FFMI) or skeletal frame models (like the Casey Butt formula) to establish their peak ideal body weight. In these contexts, carrying a higher total body weight is considered optimal, provided the excess mass is strictly lean muscle tissue rather than adipose storage.

Why Ideal Weight Matters

Ideal Weight: Health & Longevity Implications

Optimising your Ideal Weight result is directly connected to the following biological and longevity markers:

Cardiovascular StrainExceeding your ideal weight range by 20% or more doubles the risk of hypertension and increases left ventricular wall thickness, reducing heart efficiency during physical exertion.

Metabolic FlexibilityOperating within your ideal weight range is associated with superior mitochondrial efficiency — the body oxidises fuel more cleanly, resulting in higher sustained energy levels and faster recovery.

Insulin SensitivityEach 10% reduction toward ideal weight from an obese baseline reduces fasting insulin levels by approximately 20%, significantly lowering the risk of metabolic syndrome progression.

Hormonal BalanceFor women, operating significantly below ideal weight suppresses hypothalamic-pituitary-ovarian axis function, disrupting menstrual cycles and reducing bone mineral density over time.

Ideal Weight Calculator Limitations

⚠Frame density classification (small, medium, large) is subjective and prone to misclassification — wrist circumference alone does not capture skeletal density
⚠Ideal weight formulas do not account for athlete muscle mass — competitive athletes may exceed 'ideal' ranges while maintaining low body fat
⚠Multiple formula variance exists (Devine, Robinson, Miller, Hamwi) — different formulas can produce 10–17% weight range differences for the same individual at taller heights

Setting Realistic Weight Goals

Safe Execution Protocol: Ideal Weight Next Steps

Before acting on your results, follow these expert-validated guidelines to protect metabolic health and long-term progress:

Ideal weight formulas are population-based averages — athletes, older adults, and individuals with high muscle mass may safely operate above the calculated range.
Target a rate of 1–2 lbs per week of weight change maximum to protect bone mineral density and prevent the rapid lean mass loss associated with crash dieting.
Frame-adjusted ideal weight ranges should always take precedence over single-formula outputs for individuals with small or large bone frames.
Consult a GP or registered dietitian if your current weight differs from the calculated ideal range by more than 20% before implementing any structured diet protocol.

Use the clinical routing dashboard below to execute these steps safely with verified professional resources.

NHLBI Weight Reference