BMI Calculator

Calculate Your BMI — Free

Enter your height and weight to calculate your Body Mass Index instantly, along with which standard weight category it falls into.

How to Calculate BMI

Enter your height and weight — in metric or imperial units, whichever you prefer — and your BMI is calculated instantly, along with the general category it falls into: underweight, normal weight, overweight, or obese.

What BMI Actually Measures

BMI is a simple ratio of weight to height, originally designed as a quick, population-level screening tool rather than a precise individual health measurement. It doesn't distinguish between muscle and fat, doesn't account for body frame, age, or muscle mass, and can be misleading for very muscular people or older adults. It's a useful starting point for a general sense of where you stand, not a diagnosis — a doctor or healthcare provider is the right source for actual health guidance.

Good Uses for This Tool

Getting a quick, general reference point for your weight relative to height, tracking how your BMI changes over time, or understanding the standard category your BMI falls into before a conversation with a healthcare provider.

Is It Actually Private?

Yes. The calculation happens entirely in your browser — nothing you enter is sent to a server.