The short version
BMI Compass is an informational tool, not a medical device or a substitute for professional advice.
Not medical advice
Nothing on this site — including your BMI figure, category label, chart, or any accompanying text — constitutes medical advice, diagnosis, or treatment. It is provided for general informational and educational purposes only. Always seek the advice of a physician, registered dietitian, or other qualified health provider with any questions you may have regarding a medical condition, your weight, or your health, and before making changes based on anything you see here.
What BMI does and doesn't measure
Body Mass Index is a simple ratio of weight to height. It's a widely used population-level screening tool, but on an individual level it has real, well-documented limitations:
- It doesn't distinguish between muscle, fat, and bone mass — a muscular or athletic person can register as "overweight" despite low body fat.
- It doesn't account for age, sex, ethnicity, pregnancy, or body composition changes that come with ageing.
- It says nothing about where fat is distributed, which matters for health risk (visceral vs. subcutaneous fat, for instance).
- It is one screening signal among many — blood pressure, blood sugar, cholesterol, family history, and how you actually feel all matter too.
The colour-coded ranges and category labels used throughout this app follow the World Health Organization's standard adult BMI classification (Underweight, Normal weight, Overweight, Obese). These are general population reference ranges, not a personalised assessment, and they were not designed with every body type, age group, or health condition in mind. That's also why this app offers an optional waist-to-height ratio alongside BMI — it's another simple, imperfect signal, not a replacement for BMI or for professional judgement, but one more data point that can round out the picture.
No guarantee of accuracy
BMI Compass calculates BMI using the standard formula from the height and weight you enter yourself. We don't verify, audit, or validate the numbers you type in, and calculations, charts, and category thresholds are provided "as is" without warranty of any kind, express or implied. Use the results as a rough, private reference point — not as a clinical measurement.
Talk to a professional
If you have concerns about your weight, your health, or a pattern you're seeing in your tracked data, the right next step is a conversation with a doctor or other qualified clinician who knows your full health picture — not a self-diagnosis based on this or any other online tool. If you are experiencing symptoms that concern you, please seek appropriate medical care rather than relying on this app.
Limitation of liability
To the fullest extent permitted by law, the creators of BMI Compass accept no liability for any decision made, or action taken, in reliance on the information provided by this app. Your use of this site is at your own discretion and risk.