What is a healthy BMI range?

A BMI between 18.5 and 24.9 is considered the normal or healthy weight range for adults. Below 18.5 is underweight, 25.0–29.9 is overweight, and 30 or above is classified as obese by standard medical definitions.

Is BMI accurate for everyone?

Not entirely. BMI doesn't account for muscle mass, bone density, age, or fat distribution. Athletes often register as overweight due to muscle mass, while some people with a 'normal' BMI may carry excess visceral fat. It's a useful population screening tool but not a personal health diagnosis.

How do I calculate BMI manually?

In metric: BMI = weight (kg) / height (m)². For example, 70 kg at 1.75 m gives 70 / (1.75 × 1.75) = 22.9. In imperial: BMI = (weight in lbs × 703) / height in inches².

Does BMI differ for children?

Yes. For children and teens aged 2–19, BMI is plotted on age- and sex-specific growth charts. The same number means different things at different ages. This calculator is designed for adults.

What is the ideal weight range for my height?

The ideal weight range is the weight span that corresponds to a BMI of 18.5–24.9 for your height. The calculator shows this range automatically in both kg and lbs once you enter your height.

BMI计算器

使用公制或英制单位计算体重指数(BMI)，即时查看BMI类别和适合您身高的理想体重范围。

单位制

体重

身高

输入体重和身高即可计算BMI。

使用方法

使用公制或英制单位计算体重指数(BMI)，即时查看BMI类别和适合您身高的理想体重范围。

1Select your preferred unit system — Metric (kg and cm) or Imperial (lbs and feet/inches) — using the toggle at the top.
2Enter your weight. In metric, type kilograms. In imperial, type pounds.
3Enter your height. In metric, type centimeters. In imperial, enter feet and inches separately in the two fields.
4Your BMI appears instantly with a color-coded result: blue for underweight, green for normal, amber for overweight, and red for obese.
5Check the BMI scale bar to see where your number falls visually, and the ideal weight section to see the healthy weight range for your height.

主要功能

Metric and imperial support — switch between kg/cm and lbs/ft-in with a single click
Color-coded BMI categories — instant visual feedback with blue/green/amber/red coding
Visual BMI scale bar — see exactly where your BMI falls on the full 10–40+ range
Ideal weight range — shows the healthy weight range for your height in both kg and lbs
Instant calculation — results update live as you type, no button required

常见问题

了解更多

BMI Calculator — What Your Number Actually Means (And What It Doesn't)