Find out if your weight is in a healthy range for your height. Instant results, no signup required.
Calculate BMI ↓BMI is calculated as weight (kg) divided by height (m) squared.
A BMI below 18.5 may point to insufficient calorie intake, an underlying health condition, or a naturally lean build. Common risks include reduced immune function, fatigue, and in women, irregular menstrual cycles. If this applies to you, a gradual calorie surplus of 300–500 kcal per day combined with strength training is usually recommended over rapid weight gain.
This range is associated with the lowest statistical risk of cardiovascular disease, type 2 diabetes, and other weight-related conditions for most adults. Being in this range doesn't guarantee good health on its own — body composition, diet quality, and activity level still matter — but it's a reasonable target for general wellbeing.
A BMI in this range is linked to a moderately elevated risk of high blood pressure, joint strain, and metabolic issues, though the risk varies a lot depending on where fat is stored and overall fitness. A modest calorie deficit of 300–500 kcal per day, paired with regular movement, is typically enough to shift the trend over a few months.
This range is associated with a significantly higher risk of heart disease, type 2 diabetes, sleep apnea, and joint problems. The good news: even a modest reduction of 5–10% of body weight has been shown to meaningfully improve blood pressure and blood sugar markers. We'd recommend working with a doctor or registered dietitian to build a sustainable plan rather than pursuing rapid weight loss.
Body Mass Index was developed in the 1830s by Belgian statistician Adolphe Quetelet as a way to describe body weight relative to height across large populations — not to assess any one individual's health. The formula is simple: weight in kilograms divided by height in metres squared (kg/m²). Its main appeal is that it requires no special equipment, just a scale and a tape measure, which is why it's still used as a quick screening tool by doctors and health organisations worldwide.
BMI's biggest limitation is that it can't distinguish muscle from fat. A muscular athlete and a sedentary person of the same height and weight will get the identical BMI score, even though their health profiles are completely different — this is why bodybuilders and strength athletes are frequently classified as 'overweight' or 'obese' despite low body fat. BMI is also less reliable for people over 65 (where some extra weight is protective), for pregnant women, for children and teenagers (who need age- and sex-specific growth charts instead), and it doesn't account for ethnic differences in body composition. If any of these apply to you, treat your BMI result as one data point among several — not a diagnosis.
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