General · Health
Waist-to-height ratio calculator.
Measure your waist and height to find your waist-to-height ratio (WHtR) and see your NICE central-adiposity risk category — the "keep your waist below half your height" rule, made precise.
Inputs
Your WHtR
Fill the form and press Calculate WHtR.
Understanding waist-to-height ratio
Waist-to-height ratio (WHtR) is your waist circumference divided by your height, measured in the same units. It is a simple, single central-obesity screen that does not need separate age-, sex-, or ethnicity-specific tables the way BMI and waist-to-hip ratio do — a 2010 systematic review found "WHtR may be advantageous because it avoids the need for age-, sex- and ethnic-specific boundary values."
Formula
- WHtR = waist circumference ÷ height
Risk thresholds (UK NICE guidance)
- Below 0.4: possible risk of undernutrition — worth discussing with a clinician.
- 0.4 – 0.49: healthy — no increased risk.
- 0.5 – 0.59: increased risk of central-adiposity-related health problems.
- 0.6 and above: further increased risk — consider losing weight.
The 0.5 boundary was first proposed by Ashwell & Cole in 1996 and is now the basis of the "keep your waist to less than half your height" public-health message, most recently reflected in the UK National Institute for Health and Care Excellence (NICE) obesity guideline (NG246, October 2022). Source: NICE guidance and the peer-reviewed literature it cites, as summarized on the waist-to-height ratio entry of Wikipedia (accessed 2026-09-29).
Disclaimer
This calculator is for educational purposes only and is not a substitute for professional medical advice. Consult a healthcare provider for any health assessment.