Health Tools
A quick, private way to run a standard health calculation — starting with BMI, the most commonly requested one — without creating an account on a health app or handing your weight and height to a server.
BMI Calculator computes Body Mass Index from your height and weight in either metric (cm/kg) or imperial (ft-in/lb) units, and places the result against the standard weight categories (underweight, normal, overweight, obese). It's the calculation most doctors and fitness apps use as a first, rough screening number — not a diagnosis.
BMI has real, well-documented limitations: it doesn't distinguish muscle mass from fat, so a muscular athlete can register as "overweight" by the formula despite low body fat, and it wasn't designed with every body type in mind. Use it as one quick data point, not a verdict on your health.
This category is intentionally starting small and will grow with more privacy-friendly health calculators over time, following the same rule as everything else on this site: real math, run locally, with the limitations stated plainly rather than oversold.
What you can use it for
- Get a quick BMI reading from height and weight in either metric or imperial units
- Track how BMI changes as your weight changes, without logging into a health app
- Check where a number falls against the standard BMI categories
- Do a quick health calculation without an account, app install, or data sharing
Frequently asked questions
Is BMI an accurate measure of health?
It's a rough screening tool, not a diagnosis. BMI doesn't account for muscle mass, bone density, or body composition, so an athlete or very muscular person can show a "high" BMI despite low body fat. Talk to a doctor for a fuller picture.
Is my height and weight data stored or sent anywhere?
No — the calculation runs entirely in your browser. Nothing you enter is transmitted, logged, or stored.
What BMI categories does this use?
The standard classification: underweight (below 18.5), normal weight (18.5–24.9), overweight (25–29.9), and obese (30 and above).
Does this work for children?
No — BMI-for-age percentile charts for children and teens are different from the adult BMI formula used here. This calculator is intended for adults.