Keep your waist circumference to less than half your height. That's the entire rule. Waist-to-height ratio is one of the simplest health metrics — and research suggests it predicts cardiometabolic risk better than BMI.
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The Formula
Waist-to-height ratio (WHtR) = waist circumference ÷ height. Both measurements must use the same unit (cm or inches — it doesn't matter which).
Example: Waist 82 cm ÷ Height 175 cm = 0.47 — well below the 0.5 threshold, indicating low abdominal fat risk.
How to measure your waist correctly: Measure at the midpoint between the bottom of your lowest rib and the top of your hip bone — usually around the belly button level. Measure after a normal exhale, without sucking in. Use a flexible tape measure.
Healthy Waist-to-Height Ratio Ranges
WHtR
Category
Applies to
< 0.40
Underweight / very lean
All adults
0.40–0.49
Healthy
All adults
0.50–0.59
Overweight / increased risk
All adults
≥ 0.60
Obese / high risk
All adults
Unlike BMI, WHtR uses a single threshold (0.5) that applies to all adults regardless of sex, age, or ethnicity. This is one of its major practical advantages.
WHtR identified more people at metabolic risk than BMI — including "normal-weight obese" individuals with high abdominal fat but BMI under 25.
The 0.5 threshold worked consistently across ethnicities where BMI thresholds vary (e.g. Asian populations have higher metabolic risk at lower BMIs).
WHtR requires only two measurements (waist + height) vs BMI's two (weight + height) — but waist is more informative because it captures visceral fat directly.
Why visceral fat matters: Fat stored around internal organs (visceral fat) releases inflammatory cytokines and free fatty acids directly into the portal circulation. This drives insulin resistance, dyslipidaemia, and hypertension more directly than subcutaneous fat at the hips and thighs.
WHtR Reference Table by Height
Height
Healthy waist (< 0.5)
Risk threshold (0.5)
155 cm (5'1")
< 77.5 cm / 30.5 in
77.5 cm / 30.5 in
160 cm (5'3")
< 80 cm / 31.5 in
80 cm / 31.5 in
165 cm (5'5")
< 82.5 cm / 32.5 in
82.5 cm / 32.5 in
170 cm (5'7")
< 85 cm / 33.5 in
85 cm / 33.5 in
175 cm (5'9")
< 87.5 cm / 34.5 in
87.5 cm / 34.5 in
180 cm (5'11")
< 90 cm / 35.4 in
90 cm / 35.4 in
185 cm (6'1")
< 92.5 cm / 36.4 in
92.5 cm / 36.4 in
190 cm (6'3")
< 95 cm / 37.4 in
95 cm / 37.4 in
Check your BMI and body fat estimate
Our dashboard gives you BMI, estimated body fat %, ideal weight, calorie targets and more — use it alongside your WHtR for a complete picture.
Dariusz is a software developer and fitness enthusiast who built BMI Tracker to make evidence-based health metrics accessible without the noise of modern wellness apps. The formulas and reference ranges on this site are sourced from WHO guidelines, CDC public health data, and peer-reviewed research.
Waist-to-Height Ratio vs BMI: Which Is Better?
Multiple meta-analyses have compared waist-to-height ratio (WHtR) with BMI for predicting cardiometabolic outcomes. The consistent finding: WHtR performs as well or better than BMI for predicting:
Type 2 diabetes risk
Cardiovascular disease incidence
Hypertension
Metabolic syndrome
All-cause mortality
A 2012 meta-analysis of over 300,000 participants found WHtR superior to BMI for predicting cardiometabolic risk factors. A 2020 review in Clinical Obesity concluded that WHtR should be used alongside BMI in clinical practice.
The main advantage: WHtR measures central adiposity directly. Visceral fat — the fat stored around internal organs rather than under the skin — is metabolically active and dangerous in ways that subcutaneous fat is not. BMI has no way to detect where fat is located; WHtR is a direct proxy for abdominal fat accumulation.
How to Measure Your Waist Correctly
Waist measurement is simple but frequently done incorrectly, producing readings that overestimate or underestimate actual waist circumference:
Find the correct location: Midway between the bottom of the lowest rib and the top of the hip bone (iliac crest). This is roughly at the level of the navel for most people, but the anatomical landmark is more reliable
Measure at the end of a normal exhale: Don't breathe in or suck in — the measurement should reflect your natural resting circumference
Use a flexible tape measure: Hold it parallel to the floor and snug against the skin, not compressing it
Measure twice: Take two readings and average them. Readings more than 2 cm apart suggest technique inconsistency
Measure in the morning: Before eating or drinking if possible, for consistency across measurements over time
Your height measurement should be without shoes. Both measurements in the same unit (cm or inches) — divide waist by height. The result should be below 0.5 for most adults.
Frequently Asked Questions
Below 0.5 is the widely recommended threshold — keep your waist circumference less than half your height. Some guidelines add nuance: below 0.4 is very lean; 0.5–0.59 is increased risk; 0.6 and above is high risk. There is no separate threshold for men and women, unlike waist circumference alone, which uses different cutoffs by sex.
For predicting cardiometabolic risk (type 2 diabetes, cardiovascular disease), research suggests WHtR performs as well or better than BMI. It accounts for body frame size and directly measures central adiposity. Its main advantage is that it detects abdominal fat regardless of total body weight — something BMI cannot do. Ideally use both: BMI gives overall weight context, WHtR gives fat distribution context.
The 0.5 threshold applies to both sexes — unlike waist circumference alone, which uses different cutoffs for men (94/102 cm) and women (80/88 cm). WHtR naturally accounts for body size, which is why a single threshold works across sexes. Some research suggests women may have slightly higher optimal WHtR due to natural fat distribution differences, but the 0.5 rule is the standard clinical recommendation for both.
Accumulation of abdominal fat — particularly visceral fat around internal organs. Contributors include: poor diet (high in refined carbohydrates and processed foods), sedentary lifestyle, chronic stress (cortisol promotes abdominal fat storage), disrupted sleep, hormonal changes (especially menopause in women), and genetic predisposition. Age is also a significant factor — abdominal fat accumulation tends to increase from middle age onward.
Yes — this is one of the most important situations WHtR reveals. Someone with normal weight obesity (healthy BMI but high body fat, particularly abdominal fat) may have a BMI of 22 but a WHtR above 0.5. This is associated with elevated metabolic risk despite a healthy weight. Normal-weight people with high WHtR have significantly elevated cardiovascular and diabetes risk compared to those with both metrics in the healthy range.
Abdominal fat responds well to calorie deficit and aerobic exercise — often faster than overall BMI changes. Studies show that even modest weight loss (5–10% of body weight) produces disproportionate reductions in visceral fat. A WHtR of 0.55 can realistically move below 0.5 within 3–6 months of consistent dietary and exercise changes, depending on starting point and adherence.