Free tool · Body
Waist-to-height ratio calculator
Short answer
Divide your waist measurement by your height, in the same units. NICE advises keeping your waist to less than half your height: a ratio of 0.4–0.49 is healthy, 0.5–0.59 means increased health risk and 0.6 or more means further increased risk. A 96.5 cm waist at 170 cm tall is 0.57.
Last reviewed 28 October 20262 published sourcesNot medical advice
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Get Reps freeWaist-to-height ratio calculator
Measure your waist midway between your lowest rib and the top of your hip, after breathing out.
Enter your waist and height to see your ratio.
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What the ratio means
NICE classifies central adiposity by waist-to-height ratio: 0.4 to 0.49 is healthy, 0.5 to 0.59 indicates increased health risks and 0.6 or more indicates further increased risks, including type 2 diabetes, high blood pressure and cardiovascular disease. The thresholds apply to adults of both sexes and all ethnicities with a BMI under 35, including those with high muscle mass (NICE NG246, 2025).
In a meta-analysis of 31 studies, waist-to-height ratio outperformed waist circumference and BMI as a screening tool for adult cardiometabolic risk factors (Ashwell et al., 2012).
| Height | Ratio 0.5 | Ratio 0.6 |
|---|---|---|
| 150 cm (4 ft 11 in) | 75.0 cm (29.5 in) | 90.0 cm (35.4 in) |
| 155 cm (5 ft 1 in) | 77.5 cm (30.5 in) | 93.0 cm (36.6 in) |
| 160 cm (5 ft 3 in) | 80.0 cm (31.5 in) | 96.0 cm (37.8 in) |
| 165 cm (5 ft 5 in) | 82.5 cm (32.5 in) | 99.0 cm (39.0 in) |
| 170 cm (5 ft 7 in) | 85.0 cm (33.5 in) | 102.0 cm (40.2 in) |
| 175 cm (5 ft 9 in) | 87.5 cm (34.4 in) | 105.0 cm (41.3 in) |
| 180 cm (5 ft 11 in) | 90.0 cm (35.4 in) | 108.0 cm (42.5 in) |
| 185 cm (6 ft 1 in) | 92.5 cm (36.4 in) | 111.0 cm (43.7 in) |
| 190 cm (6 ft 3 in) | 95.0 cm (37.4 in) | 114.0 cm (44.9 in) |
| 195 cm (6 ft 5 in) | 97.5 cm (38.4 in) | 117.0 cm (46.1 in) |
Measuring it well
Measure midway between the bottom of your ribs and the top of your hips, after breathing out naturally, and use the same unit for waist and height (NICE NG246, 2025). Measure at the same time of day each time if you are tracking change.
For the weight-based view, see the BMI calculator, which also explains when BMI misleads.
Build the habits that move it
Reps tracks the meals you log alongside the sleep, heart rate and workouts your Apple Watch records, so the daily habits behind your waistline are in one place.
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Common questions
How do I measure my waist for this?
NICE's method: find the bottom of your ribs and the top of your hips, wrap a tape measure around your waist midway between them (just above the belly button), breathe out naturally and read the tape. Measure your height in the same unit.
What is a healthy waist-to-height ratio?
NICE guideline NG246 classes 0.4 to 0.49 as healthy central adiposity, 0.5 to 0.59 as increased and 0.6 or more as high. The same thresholds apply to men and women of all ethnicities, including people with high muscle mass, as long as BMI is under 35.
Is waist-to-height ratio better than BMI?
It measures something BMI cannot: fat around the middle. A 2012 meta-analysis of 31 studies with more than 300,000 adults found waist-to-height ratio was better than waist circumference and BMI at picking up cardiometabolic risk factors. NICE now recommends measuring it alongside BMI.
Sources
Figures on this page were checked against these publications on 28 October 2026.
- National Institute for Health and Care Excellence. Overweight and obesity management (NG246). Section 1.9: Identifying and assessing overweight, obesity and central adiposity. 2025. www.nice.org.uk/guidance/ng246/chapter/Identifying-and-assessing-overweight-obesity-and-central-adiposity
- Ashwell M, Gunn P, Gibson S. Waist-to-height ratio is a better screening tool than waist circumference and BMI for adult cardiometabolic risk factors: systematic review and meta-analysis. Obesity Reviews. 2012;13(3):275–286. doi.org/10.1111/j.1467-789X.2011.00952.x
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