Healthy Weight Calculator

Using a healthy weight calculator is straightforward. You'll typically need three pieces of information: your height, your sex assigned at birth (since most formulas are sex-specific), and sometimes your age or body frame size. Plug those in and the calculator returns a healthy weight range based on one or more of the methods described below.

A few tips before you start:

• Measure your height without shoes for the most accurate result.
• Use the same unit system throughout. Mixing inches and centimeters or pounds and kilograms is the most common source of errors.
• If the calculator asks for frame size, a quick way to estimate it is to wrap your thumb and index finger around your wrist. If they overlap, you're small-framed; if they just touch, medium; if there's a gap, large.

The result is a reference range, not a prescription. Talk to your doctor before making any significant changes to your diet or exercise routine based on these numbers.

Your healthy weight range is the span of weights that are generally associated with good health for someone of your height and body type. Most calculators express this as a minimum and maximum, such as 130 to 160 pounds for a 5'7" adult.

Two broad approaches are used to calculate that range. The first is BMI, which compares your weight to your height using a simple formula and places you in a category. The second is ideal body weight (IBW), which uses height-based formulas developed in clinical settings. Neither method is perfect on its own, so many calculators show results from both and let you compare.

The range matters more than any single target weight. Staying anywhere within a healthy range, rather than chasing one specific number, is a much more realistic and sustainable goal.

Height is the single biggest variable in determining a healthy weight. Taller people have more bone, more muscle mass potential, and larger organ systems, all of which add weight. The relationship isn't perfectly linear, but as a general rule, every additional inch of height adds a few pounds to the healthy range.

For adults, a rough rule of thumb is that a 5'0" woman has a healthy weight range around 97 to 123 pounds, while a 5'0" man ranges from about 101 to 127 pounds. At 6'0", those ranges jump to roughly 140 to 177 pounds for women and 148 to 185 pounds for men. The exact numbers shift depending on which formula or BMI threshold you use.

Height-based charts are a quick reference, but they don't account for muscle mass, bone density, or age-related changes in body composition. Use them as a starting point, not a final answer.

Body Mass Index, or BMI, is the most commonly used tool for defining healthy weight ranges at the population level. It was developed in the 19th century by Belgian mathematician Adolphe Quetelet and later adopted by the medical community as a screening tool. It's not a direct measure of body fat, but it correlates with it well enough to be useful for most adults.

The formula is simple:

• Metric: BMI = weight (kg) ÷ height² (m²)
• Imperial: BMI = 703 × weight (lbs) ÷ height² (in²)

A BMI between 18.5 and 24.9 is classified as the normal or healthy range. From there, the calculator works backward: to find your healthy weight, you take those BMI limits and multiply by your height in meters squared. That gives you the low end (BMI 18.5) and high end (BMI 24.9) of your healthy weight window.

Ideal body weight formulas were developed in clinical settings, originally to help calculate medication dosages based on expected lean body mass rather than total weight. Over time they became general reference points for healthy weight estimation. Unlike BMI, these formulas produce a single target number rather than a range, though most practitioners treat the result as the midpoint of a reasonable range (usually plus or minus 10 percent).

The four most widely cited formulas are Devine, Robinson, Hamwi, and Miller. They all share the same basic structure: a base weight for a 5-foot-tall adult, plus an increment for each inch above 5 feet, with separate equations for men and women. The differences lie in the specific numbers used for the base and increment.

The chart below combines BMI-based healthy ranges for adults at common heights. These figures apply to both men and women using the standard BMI 18.5 to 24.9 window.

Values are rounded to the nearest pound or kilogram. If your current weight falls within this range for your height, you're generally considered to be at a healthy weight by BMI standards.

Men and women of the same height typically have different healthy weight targets. Men generally carry more muscle mass and have denser bones, which pushes their ranges slightly higher. The difference isn't dramatic at average heights, but it becomes more noticeable at the extremes of the height spectrum.

The BMI formula itself is the same for both sexes, so the BMI-based range at a given height is identical for men and women. The difference shows up in the ideal body weight formulas, which use separate equations. At 5'8", for example, the Devine formula gives a target of about 65 kg (143 lbs) for men and 60 kg (132 lbs) for women.

Body fat percentage tells a more nuanced story. A healthy body fat percentage for women is generally considered to be 20 to 32 percent, while for men it's 8 to 19 percent. Women naturally carry more essential fat due to hormonal and reproductive factors. This means two people at the same BMI can have meaningfully different body compositions depending on sex, which is one reason BMI alone has limitations.

Age also plays a role. After 40, both men and women tend to lose muscle mass and gain fat, which can keep BMI stable even as body composition shifts in an unhealthy direction. Staying within a healthy weight range while maintaining muscle through strength training becomes increasingly important with age.

Weight isn't just about calories in versus calories out, though that's a big part of it. Several factors influence what a healthy weight looks like for a specific person.

• Age: Metabolism slows gradually with age, and muscle mass tends to decrease while fat mass increases. Older adults may weigh slightly more than their younger counterparts while still being metabolically healthy.
• Sex: As noted above, men and women have different baseline body compositions, which affects where their healthy weight falls.
• Muscle mass: Muscle is denser than fat. Someone with a high muscle-to-fat ratio may weigh more than the BMI chart suggests without any health risk.
• Bone density: People with larger, denser bones legitimately weigh more. Frame size adjustments in some formulas try to account for this.
• Genetics: Your family history influences your natural body shape, where you store fat, and how your metabolism works.
• Ethnicity: Research suggests that health risks associated with higher BMI appear at lower thresholds for some Asian populations. Some guidelines use adjusted BMI cutoffs for these groups.
• Hormones: Thyroid disorders, insulin resistance, polycystic ovary syndrome (PCOS), and other hormonal conditions can significantly affect weight and body composition independent of diet and activity.

No calculator can factor all of this in automatically. These tools give you a starting point for a conversation with your healthcare provider, not a final verdict on your health.

Walking through a couple of examples makes the math more concrete.

Example 1: Woman, 5'6" (168 cm), 145 lbs (65.9 kg)

• BMI = 703 × 145 ÷ (66)² = 101,935 ÷ 4,356 ≈ 23.4. This falls in the normal/healthy range (18.5 to 24.9).
• Devine IBW = 45.5 + 2.3 × 6 = 59.3 kg (about 131 lbs). Her actual weight is about 10 percent above the Devine target, which is within the typical acceptable window.
• BMI healthy weight range at this height: approximately 115 to 154 lbs. She's well within that range.

Example 2: Man, 5'11" (180 cm), 195 lbs (88.5 kg)

• BMI = 703 × 195 ÷ (71)² = 137,085 ÷ 5,041 ≈ 27.2. This lands in the overweight category (25.0 to 29.9).
• Devine IBW = 50 + 2.3 × 11 = 75.3 kg (about 166 lbs). His actual weight is about 17 percent above the Devine target.
• BMI healthy weight range at this height: approximately 133 to 179 lbs. He's about 16 pounds above the upper end of the healthy BMI range.

These examples show how BMI and IBW formulas can tell slightly different stories. A doctor would look at both, along with waist circumference, blood pressure, blood glucose, and cholesterol, before drawing any conclusions about health risk.

BMI and ideal body weight formulas are related but not the same thing, and they're used for different purposes.

BMI is better suited for looking at trends across large groups of people or doing a quick initial screen. IBW formulas are more useful when you need a specific number, like when a pharmacist is calculating a weight-based medication dose.

For everyday personal use, neither one is perfectly accurate on its own. Using both together, and comparing where you fall in each system, gives you a more complete picture than either would alone. And if the numbers feel confusing or concerning, a registered dietitian or your primary care physician can help you interpret them in the context of your actual health.