BMI Calculator
By Santaji GadepatilinUpdated October 27, 2026
BMI vs Weight (kg) — other inputs held at your current values.
How to use this calculator
Enter your weight and height in any units — kg or lb, cm or ft — and your BMI and category appear instantly. To find a target weight, type your height and a BMI value instead; the weight is worked out for you.
The formula
BMI = weight (kg) ÷ height (m)²
Example: 70 kg and 1.72 m → 70 ÷ 1.72² = 70 ÷ 2.958 = 23.7.
BMI categories
| BMI | WHO category | Asian / Indian guideline |
|---|---|---|
| Below 18.5 | Underweight | Underweight |
| 18.5 – 22.9 | Normal | Normal |
| 23 – 24.9 | Normal | Overweight |
| 25 – 29.9 | Overweight | Obese (grade 1) |
| 30 and above | Obese | Obese (grade 2) |
The coloured bar under the BMI field uses the Asian cut-off between 23 and 25 so that both systems are visible.
Limitations
BMI is a quick screening number, not a diagnosis. It does not consider muscle mass, bone density, age, sex or where fat is stored. Pregnant women and children need different charts. Talk to a doctor for a full assessment.
Frequently asked questions
What is a healthy BMI?
The WHO classes 18.5–24.9 as normal weight. For Asian populations, including Indians, guidelines commonly use 18.5–22.9 as normal and 23 or above as overweight because health risks start at a lower BMI.
How do I find my ideal weight for a target BMI?
Type your height and the target BMI (for example 22). The weight field is calculated automatically.
Is BMI accurate for athletes?
Not always. BMI cannot tell muscle from fat, so muscular people can show a high BMI while being healthy. Waist circumference adds useful context.