What Should I Weigh at 5'8"?
Short answer: at 5'8" (172.7 cm), a healthy adult weight is 122 lbs to 164 lbs — 55.2–74.5 kg — which is the WHO BMI band of 18.5 to 24.9. There is no single target weight inside that band.
Where each boundary falls at 5'8"
The table below converts the WHO BMI thresholds into actual weights for this height, so you can see exactly how much room you have on either side.
| BMI threshold | Weight at 5'8" | Boundary | What it means |
|---|---|---|---|
| BMI 18.5 | 122 lbs (55.2 kg) | Underweight boundary | Below this weight, BMI falls under 18.5 |
| BMI 25 | 164 lbs (74.6 kg) | Overweight boundary | At or above this weight, BMI reaches 25.0 |
| BMI 30 | 197 lbs (89.5 kg) | Obesity boundary | At or above this weight, BMI reaches 30.0 |
| BMI 35 | 230 lbs (104.4 kg) | Obesity class II boundary | At or above this weight, BMI reaches 35.0 |
What the four clinical formulas say
Before BMI ranges became standard, clinicians used per-height formulas to pick a single "ideal" weight. They disagree with each other by several kilograms, which is itself the point: a range is a more honest answer than a number.
| Method | Men | Women |
|---|---|---|
| WHO BMI band (18.5–24.9) | 122 lbs–164 lbs | 122 lbs–164 lbs |
| Devine (1974) | 151 lbs | 141 lbs |
| Robinson (1983) | 148 lbs | 138 lbs |
| Miller (1983) | 149 lbs | 141 lbs |
| Hamwi (1964) | 153 lbs | 139 lbs |
These formulas were derived for drug dosing and actuarial tables, not for setting personal goals. Where they disagree with the BMI band, the BMI band is the better reference for adults.
WHO adult BMI categories
The World Health Organization defines adult BMI categories using the following thresholds. These apply to adults 18–65 and are not adjusted for sex, ethnicity, or athletic status.
| Category | BMI | Population signal |
|---|---|---|
| Underweight | < 18.5 | Screen for nutritional or clinical cause |
| Normal weight | 18.5 – 24.9 | Lowest all-cause mortality band |
| Overweight | 25.0 – 29.9 | Moderate risk; strongly modified by fitness |
| Obese Class I | 30.0 – 34.9 | Clinically meaningful cardiometabolic risk |
| Obese Class II | 35.0 – 39.9 | Structured treatment usually recommended |
| Obese Class III | ≥ 40.0 | Multidisciplinary care indicated |
The BMI formula (and how this site rounds it)
Metric: BMI = weight in kilograms ÷ (height in metres)². Imperial: BMI = 703 × weight in pounds ÷ (height in inches)². Both produce the same number; 703 is the unit-conversion constant.
Worked example. An adult weighing 85 kg at 180 cm: 180 cm = 1.80 m, and 1.80² = 3.2400. 85 ÷ 3.2400 = 26.2, which is overweight. The imperial route (187 lbs, 71 in) gives 703 × 187 ÷ 71² = 26.1 — the same value within rounding.
Rounding rules used here: the WHO category is always assigned from the unrounded BMI; the value shown is that same BMI rounded to one decimal for display only. Healthy weight bounds are the exact weights at BMI 18.5 and BMI 25, rounded inward, so the pound above the stated maximum is always the first overweight pound. Pound equivalents use 1 kg = 2.20462 lbs; height in feet and inches is rounded to the nearest inch.
| Weight | Height | BMI | WHO category |
|---|---|---|---|
| 70 kg (154 lbs) | 175 cm (5'9") | 22.9 | Normal weight |
| 60 kg (132 lbs) | 165 cm (5'5") | 22.0 | Normal weight |
| 85 kg (187 lbs) | 180 cm (5'11") | 26.2 | Overweight |
| 55 kg (121 lbs) | 160 cm (5'3") | 21.5 | Normal weight |
| 78 kg (172 lbs) | 170 cm (5'7") | 27.0 | Overweight |
| 95 kg (209 lbs) | 185 cm (6'1") | 27.8 | Overweight |
Two checks that add more than the scale
- Waist circumference. Keeping your waist under half your height — roughly 34 inches (86 cm) at 5'8" — tracks abdominal fat, which BMI cannot see.
- Direction of travel. A stable weight anywhere in the healthy band is a better signal than a number that swings toward a target and back.
What BMI does not measure
BMI uses only height and weight. It is a screening ratio, not a body-composition measurement or a diagnosis. Specifically, BMI cannot tell you:
- Muscle versus fat. Weight from muscle and weight from fat count identically, so trained athletes are frequently classified as overweight at healthy body-fat levels.
- Where fat is stored. Visceral (abdominal) fat carries far more cardiometabolic risk than subcutaneous fat, and BMI is blind to the difference. Waist circumference adds that missing signal, using sex-specific thresholds — 94 cm for men and 80 cm for women (WHO, 2008). These cut-offs come mainly from European-origin populations; WHO notes equivalent risk at lower waist values in South Asian, Chinese and Japanese populations.
- Bone density or hydration. Both shift scale weight without changing fat mass.
- Age-related body change. Muscle mass declines with age (sarcopenia), so the same BMI at 70 usually represents more fat than at 25.
Where adult BMI does not apply at all: children and teenagers under 18 (who need age-and-sex percentile charts, not adult thresholds), pregnant and breastfeeding women, people with significant oedema or ascites, and adults with limb loss or skeletal dysplasia. Separately, the WHO recommends additional action points at BMI 23 and 27.5 for South Asian and East Asian adults (WHO expert consultation, Lancet 2004;363:157-63). Those are public-health intervention points, not a redefinition of the standard categories used on this site.
Frequently asked questions
What Should I Weigh at 5'8"?
A 5'8" (172.7 cm) adult sits inside the WHO healthy BMI band of 18.5–24.9 at 122 lbs (55.2 kg) to 164 lbs (74.5 kg). There is no single correct weight inside that band — a 19 kg spread is normal and healthy.
Should I aim for the midpoint?
Not necessarily. The midpoint at this height is 143 lbs (64.9 kg), but where you sit within the band depends on muscle mass, frame size and body-fat distribution. A muscular adult can sit at the top of the band with low body fat; a sedentary adult can sit mid-band with high body fat.
Do men and women have different target weights at this height?
The WHO BMI thresholds are identical for both sexes, so the 122 lbs–164 lbs band applies to both. The older clinical formulas do differ: at 5'8" they range from about 138 lbs to 153 lbs across Devine, Robinson, Miller and Hamwi, with the women's variants sitting lower.
What if I am just above the range?
Being a few pounds over the boundary is a screening signal, not a diagnosis. At 5'8", BMI 25.0 is reached at 164 lbs (74.6 kg). Waist circumference is the more informative second check: keeping your waist below half your height (about 34 inches / 86 cm here) is the measure NICE recommends alongside BMI for adults with a BMI under 35.
How was this range calculated?
BMI = weight in kilograms ÷ height in metres squared. Rearranged for weight: weight = BMI × height². At 172.7 cm (1.7269999999999999 m), BMI 18.5 gives 55.2 kg and BMI 24.9 gives 74.3 kg. Every number on this page comes from that formula, not from a lookup table.