Your bathroom scale can’t tell you where you carry weight, and for long-term health that matters more than the number itself. Fat stored around the middle is the type most closely linked with type 2 diabetes, high blood pressure and heart disease. The simplest way to check it needs a tape measure and thirty seconds: your waist-to-height ratio.
Executive Brief
- The metric: your waist divided by your height, both in the same units.
- The target: keep your waist to less than half your height, a ratio under 0.5. This is the UK’s NICE guidance for adults.
- Why it beats BMI alone: it measures where fat sits, not just total weight, so it isn’t thrown off by muscle.
Calculate Your Ratio
Waist-to-Height Ratio
A 30-second check on where you carry weight
Bands from NICE guideline NG246 for adults with a BMI under 35. Not for use in pregnancy. A screening measure, not a diagnosis. Nothing you enter is stored.
How to Measure Your Waist
- Stand upright, feet together, and find your lowest rib and the top of your hip bone.
- Wrap the tape around your waist midway between the two. For most people this is close to the belly button, not where your trousers sit.
- Breathe out normally and read the tape. Keep it snug and level, without pulling it tight.
Measure your height without shoes. Take each measurement twice and use the average if they differ.
What Your Result Means
| Ratio | NICE classification | What it indicates |
|---|---|---|
| 0.40 to 0.49 | Healthy | No increased health risk from this measure |
| 0.50 to 0.59 | Increased | Increased health risk |
| 0.60 or more | High | Further increased health risk |
NICE recommends these bands for adults with a BMI under 35, and for men and women alike.[1] A systematic review of studies covering more than 300,000 adults found waist-to-height ratio was a better screening tool for cardiometabolic risk than waist circumference or BMI alone.[2] It is a screening measure, not a diagnosis: it tells you whether a conversation with your GP is worth having.
What Moves the Number
Your ratio responds to the same fundamentals that drive long-term health. Regular aerobic exercise is one of the most reliable ways to reduce fat stored around the middle, and steady Zone 2 training is an easy way to accumulate it in a full diary. Strength training preserves the muscle that keeps your metabolism working. Chronic stress and short sleep both push in the wrong direction, so the cortisol briefing is relevant here too. If exercise alone isn't shifting things, see why exercising doesn't always mean losing weight.
Re-measure every four to six weeks, at the same time of day. Waist size changes slowly, and a monthly trend tells you far more than any single reading.
Turn One Number Into a Plan
The Executive Longevity Blueprint is our 90-day manual for the high-performing professional: movement, sleep, metabolic health and recovery, built around a full diary.
This calculator is for general information and does not replace personalised medical advice. It is designed for adults and is not suitable during pregnancy. Your measurements are calculated in your browser and are not stored or sent anywhere. Speak to your GP if you are concerned about your result.
Evidence & References
- National Institute for Health and Care Excellence (2025). Overweight and obesity management. NICE guideline NG246. View guideline
- Ashwell M, Gunn P, Gibson S (2012). 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, 13(3), 275–286. doi:10.1111/j.1467-789X.2011.00952.x