BMI Calculator
Calculate your Body Mass Index instantly. See your category, healthy weight range, BMI Prime, and a visual gauge — with WHO or Asian population guidelines.
More than a basic BMI box
Five companion tools competitors often skip — built for real planning, not just a single number.
Target Weight Calculator
Enter your height and goal BMI — get the exact weight to reach.
Ideal Weight Calculator
Robinson, Miller, Devine, and Hamwi formulas plus healthy BMI range.
Body Fat Calculator
US Navy method using neck, waist, and hip measurements — more useful than BMI alone.
BMI Chart
Print-friendly height/weight reference table for quick lookups.
Child BMI Calculator
Age- and sex-adjusted BMI categories for children and teens (2–17).
What BMI measures — and what it does not
Body Mass Index (BMI) is weight relative to height. Doctors and public-health agencies use it as a quick screening tool for weight categories that correlate with certain health risks at the population level.
It does not measure body fat directly, bone density, hydration, or muscle mass. Two people with the same BMI can have very different body compositions. That is why we also offer a Navy body-fat estimator and an ideal weight calculator using multiple clinical formulas.
WHO vs Asian BMI guidelines
Research shows that Asian populations may experience elevated cardiometabolic risk at lower BMI values. The WHO Western Pacific Region suggests overweight at BMI ≥ 23 and obesity at ≥ 27.5 for many Asian adults. Our toggle lets you switch guidelines without leaving the page.
Privacy by design
Your height and weight never leave your device. Open your browser Network tab while calculating — after the page loads, there are no outbound requests with your data. We do not require accounts, emails, or app installs.
Frequently asked questions
How is BMI calculated?
BMI equals weight in kilograms divided by height in meters squared. For imperial units: BMI = 703 × weight (lb) ÷ height (in)². It is a screening index, not a direct body-fat measurement.
What is a healthy BMI?
For most adults, WHO defines normal weight as BMI 18.5–24.9. For many Asian populations, WHO Western Pacific guidance uses 18.5–22.9 as normal and 23+ as overweight. Our calculator supports both standards.
Is BMI accurate for athletes?
No. BMI cannot distinguish muscle from fat. A muscular athlete may register as overweight despite low body fat. For athletes, combine BMI with waist circumference, body-fat percentage, or clinical assessment.
Do you store my height or weight?
No. Every calculation runs entirely in your browser. Your measurements are never sent to our servers. Optional last-result storage uses your device localStorage only.
Can I use this during pregnancy?
Standard adult BMI categories do not apply during pregnancy. Use pre-pregnancy BMI with your obstetric care team for weight-gain guidance.
Is this calculator free?
Yes — 100% free, no sign-up, no download. The site may show unobtrusive ads to stay online.