Waist-to-Height Ratio Calculator
Divide your waist by your height. Under 0.5 is the healthy threshold, which makes the rule easy to remember: keep your waist under half your height.
Your results
Measure consistently: morning, before eating, tape snug but not compressing, standing relaxed. Consistency of technique matters more than which landmark you choose. Risk categories are population associations, not a diagnosis.
Why this beats BMI
BMI cannot distinguish muscle from fat, and it takes no account of where fat sits. A muscular lifter and a sedentary person of identical height and weight get the same BMI.
Waist-to-height ratio measures central adiposity — fat around the organs — which is the fat distribution most strongly associated with metabolic and cardiovascular risk. It correlates better with those outcomes than BMI does, and it needs nothing but a tape measure.
It is also self-normalising for height, which is why a single threshold works across the population rather than needing separate charts.
Using it while training
- Waist circumference alone is the best fat-loss tracking measure you have — noise of about ±1 cm against an eight-week signal of 3–6 cm.
- Read it against your limbs. Waist down with arms and thighs holding is fat loss with muscle retention. Waist up without limb growth is fat gain.
- Very lean, heavily trained people may see the ratio stop falling as trunk musculature thickens — heavy squatting and deadlifting genuinely do that.
- Measure fortnightly, not weekly. Circumferences change slowly.
Common questions
What is a healthy waist-to-height ratio?
Under 0.5. Between 0.5 and 0.6 indicates increased risk, and 0.6 or above high risk.
Is waist-to-height better than BMI?
For individual assessment, yes — it accounts for fat distribution and is not fooled by muscle mass.
Where exactly do I measure my waist?
At the navel, horizontal, standing relaxed after a normal breath out. Consistency matters more than the exact landmark.
Does it differ by sex?
The 0.5 threshold applies broadly to both, which is part of its appeal.
Related calculators
Track the numbers, not just calculate them
MyFitsy stores your weight, measurements and every session, so the figures above become a trend instead of a one-off.
