Free BMI Calculator
Calculate your Body Mass Index and health category. 100% in your browser.
How It Works
Calculates your Body Mass Index from weight (kg) and height (cm), classifying your result into WHO health categories: underweight, normal, overweight, or obese. The tool also shows the healthy weight range for your height. All calculations are instant and happen entirely in your browser.
When to Use It
- Quick health screening to understand your weight category during fitness planning.
- Tracking BMI changes over time as part of a weight management program.
- Estimating healthy weight ranges for a given height before setting fitness targets.
Frequently Asked Questions
How is BMI calculated?
BMI equals weight in kg divided by height in meters squared (kg/m2). A 70kg person at 175cm has BMI 22.9. The tool handles all conversions when you enter kg and cm.
Is BMI accurate for athletes?
BMI has limitations for muscular individuals since muscle weighs more than fat. An athlete may show "overweight" despite low body fat. Body fat percentage provides more accuracy in such cases.
What are the WHO categories?
Underweight below 18.5, Normal 18.5-24.9, Overweight 25-29.9, Obese 30+. These are general health indicators; individual health depends on many factors beyond BMI.
All calculations happen in your browser. No data is sent to any server.
These tools are free forever. SARA takes it further.
SARA is your AI agent on WhatsApp: answers customers, takes bookings, follows up — 24/7, automatically. Try it free for 14 days.
Start your free 14-day trial →