Waist-to-Height Ratio Calculator
By Santaji GadepatilinUpdated October 27, 2026
Waist-to-height ratio is a simple measure of central fat. Keeping your waist below half your height is a good general target.
How to use the waist-to-height ratio calculator
Enter your waist and height in the same or different units. Your ratio and risk category appear instantly. To find the maximum healthy waist for your height, press × on Waist and type 0.5 as the ratio.
Waist-to-height ratio formula
WHtR = waist ÷ height
Worked example
Waist 85 cm, height 178 cm:
WHtR = 85 ÷ 178 = 0.478 → healthy (below 0.5)
The maximum healthy waist for this height is 178 × 0.5 = 89 cm.
Healthy waist size by height
| Height | Healthy | Increased risk | High risk |
|---|---|---|---|
| 150 cm (4′11″) | below 75 cm (29.5 in) | 75–90 cm | 90 cm or more |
| 160 cm (5′3″) | below 80 cm (31.5 in) | 80–96 cm | 96 cm or more |
| 170 cm (5′7″) | below 85 cm (33.5 in) | 85–102 cm | 102 cm or more |
| 180 cm (5′11″) | below 90 cm (35.4 in) | 90–108 cm | 108 cm or more |
| 190 cm (6′3″) | below 95 cm (37.4 in) | 95–114 cm | 114 cm or more |
The cut-offs of 0.5 and 0.6 follow the 2022 NICE guideline in the UK, which advises adults to keep their waist to less than half their height.
Why waist size matters
Fat stored around the abdomen (visceral fat) is linked with type 2 diabetes, high blood pressure and heart disease, even in people with a normal BMI. Waist-to-height ratio captures this, and it works across different ethnic groups and for both men and women.
Waist-to-height for children
The same 0.5 boundary is often used for children over 5, which makes it simpler than BMI percentiles. Measure in the same way and ask your doctor if the ratio is above 0.5.
Reducing your ratio
- Regular aerobic activity and strength training reduce abdominal fat.
- Cutting back on sugary drinks, refined carbohydrates and alcohol helps.
- Sleep and stress also affect where fat is stored.
Re-measure every 4–6 weeks, at the same time of day.
Categories
| WHtR | Meaning |
|---|---|
| Below 0.4 | Take care — may be underweight |
| 0.4 – 0.49 | Healthy |
| 0.5 – 0.59 | Increased health risk |
| 0.6 and above | High health risk |
UK NICE guidance (2022) recommends keeping waist size to less than half of height.
This is a screening tool. Speak to a doctor about your individual health.
Frequently asked questions
What is a healthy waist-to-height ratio?
Below 0.5 — in other words, keep your waist to less than half your height. This simple rule works for adults of any sex and most ethnic groups.
Is WHtR better than BMI?
It is a better indicator of belly fat, which is linked to heart disease and diabetes. Many researchers suggest using it alongside BMI.
Where do I measure my waist?
Midway between the bottom of your ribs and the top of your hip bones, after breathing out normally.
What is the waist-to-height ratio for a 5′6″ person?
Height 168 cm, so keep your waist below 84 cm (33 inches) for a ratio under 0.5.
Should I measure over clothing?
No. Measure on bare skin, midway between the lowest rib and the top of the hip bone, after breathing out normally.