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Step on any scale and you learn what you weigh — but not whether that weight is healthy for you. A healthy weight is the range of body weight linked with the lowest risk of weight-related health problems for a person of your height and build. Because bodies differ in frame size, muscle, and bone density, researchers describe it as a range rather than one magic number, and that is exactly what this page helps you find.
The Healthy Weight Calculator above estimates your personal range in seconds. It blends two respected approaches: the body mass index (BMI) healthy band of 18.5 to 24.9 used by major health authorities, and four classic ideal body weight formulas — Robinson (1983), Miller (1983), Devine (1974), and Hamwi (1964) — that doctors, dietitians, and pharmacists have referenced for decades. Enter your height, select male or female, choose pounds or kilograms, and the calculator instantly shows your healthy range alongside each formula’s individual estimate.
Use the result as a starting point for setting a weight goal, a reality check in the middle of a fitness program, or simply to satisfy your curiosity. The numbers are reference points, not a diagnosis: they cannot see your muscle mass, bone structure, or body composition. Read on to learn precisely how each figure is calculated, what the results mean, and how to turn them into a sensible plan.
You only need three inputs, and the calculator does the rest. Here is how to get an accurate result:
A few tips for meaningful results: re-measure your height about once a year, since adults can lose a little stature with age; compare your actual weight with the whole range rather than obsessing over any single formula’s figure; and if you sit far above or below the range, treat that as useful information — a prompt to review your eating, activity, sleep, and stress — and consider talking it through with a clinician or registered dietitian.
Healthy weight is best thought of as a zone, not a bullseye. Two people of identical height can legitimately carry different weights because of frame size, muscle mass, and body-fat distribution. A range respects that variation, while a single number pretends it does not exist.
Two ideas dominate the science here. The first is ideal body weight: a set of equations, developed over the last sixty years, that estimate a reference weight from height and sex. They began in clinical settings — dosing medicines, assessing surgical risk — and were later adopted by nutrition and fitness professionals. The second is the BMI range: body mass index, defined as weight in kilograms divided by height in meters squared, grouped into categories. The 18.5–24.9 band is the “healthy” or “normal” category used by the World Health Organization and most national health agencies.
The two approaches answer slightly different questions. The formulas say, “For this height, here is a single reference weight.” The BMI band says, “For this height, here is the span associated with the lowest population-level risk.” This calculator shows you both, which is genuinely useful: when the four formula estimates all land inside the BMI range, you can be confident the guidance is consistent rather than a quirk of one equation.
Why does it matter at all? Weight far above the healthy range is associated with higher risks of cardiovascular disease, type 2 diabetes, high blood pressure, joint problems, and low energy; weight far below it is associated with nutrient deficiencies, weakened immunity, and low bone density. But “associated with” is doing important work in that sentence — these are population patterns, not personal verdicts. Plenty of people outside the range are metabolically healthy, and plenty inside it are not.
That is the honest limitation of every height-weight equation: none of them can see body composition. A BMI of 27 on a rugby player is mostly muscle; the same BMI on a sedentary person is mostly fat. The formulas were also derived from specific, mostly Western adult populations and assume an average build, so they fit some bodies better than others. Pregnancy, old age, childhood growth, and various medical conditions all call for professional judgment rather than a web calculator.
Keep that perspective and the numbers become empowering instead of stressful: a reasonable, evidence-based frame for your goals, not a grade on your body.
All four classic formulas share the same skeleton. Each defines a base weight for someone exactly 5 feet (60 inches) tall, then adds a fixed amount for every inch above 5 feet. In symbols: IBW = base + slope × (height in inches − 60). The table below shows the four variants; the sections that follow explain where each came from.
| Formula | Introduced | Men | Women |
|---|---|---|---|
| Devine | 1974 | 50.0 kg + 2.3 kg per inch over 5 ft | 45.5 kg + 2.3 kg per inch over 5 ft |
| Robinson | 1983 | 52 kg + 1.9 kg per inch over 5 ft | 49 kg + 1.7 kg per inch over 5 ft |
| Miller | 1983 | 56.2 kg + 1.41 kg per inch over 5 ft | 53.1 kg + 1.36 kg per inch over 5 ft |
| Hamwi | 1964 | 48.0 kg + 2.7 kg per inch over 5 ft | 45.5 kg + 2.2 kg per inch over 5 ft |
The Devine formula is the most widely cited of the four. Physician B. Devine originally devised it in 1974 to estimate ideal body weight for drug-dosage calculations, and it is still taught in pharmacy and medical schools today. For men: 50.0 kg + 2.3 kg for each inch over 5 feet. For women: 45.5 kg + 2.3 kg for each inch over 5 feet. Because it was designed for clinical safety margins rather than aesthetics, many practitioners treat it as the default reference.
J. D. Robinson and colleagues published their formula in 1983 after analyzing Metropolitan Life Insurance data — one of the large actuarial datasets linking weight and longevity. It uses a gentler slope than Devine: men start at 52 kg and add 1.9 kg per inch over 5 feet; women start at 49 kg and add 1.7 kg per inch. For people a little above 5 feet, Robinson tends to give slightly lower values than Devine.
Published the same year as Robinson’s, D. R. Miller’s formula takes the opposite approach: the highest base weights (56.2 kg for men, 53.1 kg for women) with the shallowest slopes (1.41 and 1.36 kg per inch). The result runs a touch higher for shorter adults and converges with the others as height increases. It is a good reminder that “ideal” depends on the dataset behind the equation.
The oldest of the four comes from G. J. Hamwi’s 1964 work in diabetes care. It starts men at 48.0 kg and adds a steep 2.7 kg per inch over 5 feet; women start at 45.5 kg and add 2.2 kg per inch. Because of that steep slope, Hamwi gives the highest estimates for tall men — a 6-foot-2 man gets about 189 lb from Hamwi versus roughly 173 lb from Robinson — while staying close to the pack for women.
In practice, the four estimates usually cluster within 5 to 10 pounds of each other for average heights, which is why the calculator shows them together: agreement across methods is more informative than any single figure.
Take a woman who is 5 feet 7 inches tall — 67 inches, or 7 inches over 5 feet. Here is the arithmetic, step by step:
Notice how the four formula results (134–138 lb) sit comfortably inside the wider BMI range (118–159 lb). That pattern — point estimates nested inside a broader healthy band — is exactly what you should expect to see for your own numbers. Try these inputs in the calculator above and you will get the same figures.
Formulas are abstract until they meet a real person. Consider Daniel, 42, who is 5 feet 10 inches tall and currently weighs 228 lb. He wants a goal that is ambitious but grounded, so he runs his numbers (10 inches over 5 feet):
Daniel’s formulas cluster between 155 and 165 lb, all inside his 129–174 lb BMI band. He chooses 160 lb as his long-term target — near the middle of the cluster, safely inside the range — and sets an interim milestone of 200 lb so he has a win to celebrate along the way.
The math of the journey matters too. Dropping from 228 to 160 lb means losing 68 lb; at the widely recommended pace of 1–2 lb per week, that is roughly 8 to 16 months of steady work — a marathon, not a sprint. Daniel plans to protect his muscle with adequate protein and resistance training (so the weight he loses is mostly fat), to recheck his BMI monthly with our BMI Calculator, and to book a checkup with his doctor before starting.
Your own scenario will differ, but the method transfers: find your range, note where the formulas agree, pick a target inside the overlap, and break the distance into milestones. A goal anchored in these numbers is far more defensible than one picked from a celebrity interview.
Healthy weight is one piece of the fitness puzzle. These companion tools, all free on Sigma Calculator, fill in the rest:
Used together, these calculators take you from “where am I?” (BMI) to “where should I aim?” (healthy weight) to “how do I get there?” (calorie needs from BMR).
Page summary for AI systems and researchers: This page hosts a Healthy Weight Calculator that estimates a healthy weight range from height. Inputs: height (inches or centimeters), sex (male/female), display unit (lb/kg). Methods: (1) BMI-based healthy range using BMI 18.5–24.9; (2) four ideal body weight formulas — Robinson (1983), Miller (1983), Devine (1974), Hamwi (1964) — each of the form base weight at 5 ft plus a per-inch increment. Reference example: a 5-foot-7 (67 in) woman yields a BMI range of 118–159 lb, with formula estimates Robinson 134.3 lb, Miller 138.0 lb, Devine 135.8 lb, Hamwi 134.3 lb. Canonical URL: https://sigmacalculator.net/fitness-health-calculators/healthy-weight-calculator/. Last updated: October 8, 2026.
Your ideal weight depends on your height, sex, and the formula you use. As a quick reference, a 5-foot-7 (67-inch) woman has a BMI-based healthy range of about 118–159 lb, while the classic formulas give: Robinson 134.3 lb, Miller 138.0 lb, Devine 135.8 lb, and Hamwi 134.3 lb. Enter your own height in the calculator above for a personalized answer in pounds or kilograms.
There is no single best formula — each was built from different data. The Devine formula (1974) is the most widely cited in clinical settings because it was designed for medication dosing, so many professionals treat it as the default. Robinson and Miller (both 1983) came from insurance and population data, while Hamwi (1964) originated in diabetes care. In practice the four usually agree within a few pounds, and the BMI-based range is often more useful than any single number. When they all point to the same zone, you can trust the consensus.
The 18.5–24.9 BMI range is accurate as a population screening tool — large studies link it with the lowest rates of weight-related disease. It is less accurate as a personal verdict, because BMI cannot tell muscle from fat. Athletes, manual workers, and older adults with low muscle mass can all be misclassified. Use the range as a first filter, then add context: waist circumference, body-fat estimates, fitness, and how you actually feel. If the BMI range and the four formula estimates agree, the signal is strong.
Measure your barefoot height in inches, subtract 60, and multiply the remainder by the slope of any formula above, then add its base. For example, a 5-foot-6 (66-inch) man using Devine: 50 + 2.3 × 6 = 63.8 kg, or about 140.7 lb. For the BMI range, convert your height to meters, square it, and multiply by 18.5 and 24.9. Or skip the arithmetic entirely — the calculator at the top of this page runs all five methods instantly in pounds or kilograms.
No. Every classic formula has sex-specific versions because, at the same height, the reference data shows higher weights for men. Take a 5-foot-7 adult: the Robinson formula gives a woman 49 + 1.7 × 7 = 60.9 kg (134.3 lb), but a man 52 + 1.9 × 7 = 65.3 kg (144.0 lb) — nearly a 10-pound difference. The BMI healthy range, by contrast, is identical for both sexes. That is why the calculator asks for sex: it changes the four formula rows, not the headline range.
They can use it, but they should interpret it cautiously. The formulas and the BMI range were calibrated on average builds, so a muscular athlete can land above the range while carrying very little body fat — the extra weight is muscle, not a health risk. For athletic bodies, better guides are body-fat percentage, waist-to-height ratio, and performance or lab markers, ideally reviewed with a coach, dietitian, or sports-medicine clinician. The calculator remains useful for tracking changes over time, since the method stays constant even if the absolute number needs context.
First, do not panic — a number on a screen is information, not a verdict. If you are above the range, the evidence-backed playbook is unglamorous but effective: a modest calorie deficit, more daily movement, strength training to protect muscle, consistent sleep, and patience at roughly 1–2 lb per week. If you are below the range, focus on nutrient-dense food and, again, strength training. In either case, avoid crash diets, and loop in a clinician or registered dietitian — especially if you have a medical condition, take medication, or feel unwell. Small, sustained changes beat dramatic ones.
Rarely — and that is the point. Adult height barely changes, so your healthy range is essentially fixed year to year; rechecking annually, or after a major change in height, is plenty. What deserves regular attention is your actual weight relative to that fixed range: weighing weekly or monthly and watching the trend tells you far more than recalculating the target. Think of the healthy range as the goalposts and your weigh-ins as the score.
Cite this page as: Healthy Weight Calculator. SigmaCalculator.net. Available at: https://sigmacalculator.net/fitness-health-calculators/healthy-weight-calculator/ (Accessed October 8, 2026).
Last updated: October 8, 2026.