What is BMI?
Body Mass Index (BMI) is a value derived from your weight and height. Formula: BMI = weight (kg) ÷ height (m)². It gives a quick snapshot of whether you are in an underweight, healthy, overweight, or obese range.
What is a Healthy Weight for My Height?
A healthy weight corresponds to a BMI of 18.5–24.9. The calculator above shows your exact healthy weight range in kg or lbs based on your height. Most adults achieve their best health outcomes within this range.
How Much Weight Do I Need to Lose to Reach a Healthy BMI?
Once you enter your details, the calculator shows precisely how many kg or lbs you need to lose (or gain) to enter the healthy BMI range. It calculates the distance to the nearest edge of the healthy range - not an arbitrary target.
How Long Does It Take to Reach a Healthy Weight?
The calculator estimates your timeline using a safe rate of 0.5–0.8 kg (1.1–1.8 lbs) per week - the range recommended by health authorities to preserve muscle and avoid nutritional deficiencies. Faster loss is generally not sustainable.
BMI Limitations
BMI doesn't distinguish between muscle and fat mass, or account for age, sex, or body composition. Athletes may have a high BMI with low body fat. Always consider BMI alongside other health indicators and consult a healthcare professional for personalised advice.