Body Mass Index (BMI) is a simple way to check whether your weight is healthy for your height. It is commonly used by doctors, fitness professionals, and individuals to get a quick overview of body weight status.
BMI Calculator
| BMI Range | Weight Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 – 24.9 | Normal weight |
| 25.0 – 29.9 | Overweight |
| 30.0 and above | Obese |
BMI or Body Mass Index
is a simple number that shows whether your weight is in a healthy range for
your height. It’s one of the easiest ways to check if you're underweight,
normal weight, overweight, or obese.
Doctors and fitness
apps use BMI as a quick screening tool. It’s not perfect, but it gives you a
useful starting point to understand your body weight.
BMI Formula (kg and
lbs)
There are two versions
of the formula depending on which units you use.
1. Metric Formula
(kg and cm)
If your height is in
meters:
BMI = Weight (kg) ÷
Height² (m²)
If your height is in
centimeters:
BMI = Weight (kg) ÷
(Height (cm) ÷ 100)²
Example (Metric)
Weight = 60 kg
Height = 160 cm (1.60 m)
BMI = 60 ÷ (1.60 ×
1.60)
BMI = 60 ÷ 2.56
BMI = 23.44
This is considered
normal weight.
2. Imperial Formula
(lbs and inches)
If you use pounds and
inches:
BMI = (Weight (lbs)
÷ Height² (inches²)) × 703
Example (Imperial)
Weight = 132 lbs
Height = 63 inches
BMI = (132 ÷ 3969) ×
703
BMI = 0.0333 × 703
BMI = 23.41
BMI Chart Explained
Once you get your BMI
number, you can compare it with the chart below:
|
BMI |
Category |
|
Below 18.5 |
Underweight |
|
18.5 – 24.9 |
Normal weight |
|
25.0 – 29.9 |
Overweight |
|
30.0 – 34.9 |
Obese (Class I) |
|
35.0 – 39.9 |
Obese (Class II) |
|
40.0+ |
Obese (Class III) |
In simple terms:
- Under 18.5 → You may need to gain weight
- 18.5–24.9 → Healthy range
- 25–29.9 → Slightly above healthy range
- 30+ → Higher health risk
How to Calculate
BMI (Step‑by‑Step)
Metric
- Measure your weight in kilograms
- Measure your height in centimeters
- Convert height to meters (divide by 100)
- Multiply height by itself
- Divide weight by that number
Imperial
- Measure your weight in pounds
- Measure your height in inches
- Multiply height by itself
- Divide weight by that number
- Multiply the result by 703
Example BMI
Calculations
Example 1
Height: 153 cm
Weight: 60 kg
BMI = 60 ÷ (1.53 ×
1.53)
BMI = 25.63
Category: Overweight
Example 2
Height: 170 cm
Weight: 65 kg
BMI = 65 ÷ (1.70 ×
1.70)
BMI = 22.49
Category: Normal
weight
Why BMI is Useful
BMI helps you quickly understand if your weight might increase your risk
for health problems such as heart disease, diabetes, high blood pressure, joint
stress and many more. It also commonly used in health apps, clinics, and
fitness programs.
But it is important to remember that, BMI is helpful, but it doesn’t
tell the full story. It won’t know how much is your weight muscle, fat or even
body shape. Therefore, Just remember — BMI is only a general guide. Your
overall health depends on many things, including body fat, lifestyle, and
medical factors.
