Enter your weight and height to get your Body Mass Index and the standard weight category.

What BMI does and does not tell you

Body Mass Index is a single number that relates your weight to your height, used worldwide as a quick screening tool. It sorts people into broad categories from underweight to obese, which is why doctors, insurers, and public health bodies reach for it first.

Its strength is also its weakness: it is simple because it ignores everything except height and weight. It cannot tell muscle from fat, so a lean athlete can read as overweight, and it says nothing about where fat is carried. Treat BMI as a rough starting point for a conversation, not a verdict on your health.

The formula

Worked example

A person 175 cm and 70 kg has a BMI of 70 / 1.75^2 = 22.9, in the normal range.

How to read your result

Standard categories: under 18.5 underweight, 18.5 to 24.9 normal, 25 to 29.9 overweight, 30 and above obese. BMI is a rough screening tool that does not account for muscle, frame, or body composition, so it is informational and not a diagnosis.

Frequently asked questions

Is BMI accurate for everyone?

No. It does not distinguish muscle from fat, so very muscular people may read high. Use it as a rough guide.

What is a healthy BMI?

The normal range is generally 18.5 to 24.9, but individual health depends on many factors.

Is this medical advice?

No. Speak with a healthcare professional for any health decision.

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