BMI Calculator

Name: BMI Calculator
Author: Rahim Virani

Calculate your Body Mass Index instantly and see your WHO weight category — underweight, normal, overweight or obese. Free for men and women.

Units

Weight

Height

Age

years

Gender

Not medical advice — BMI is a screening tool, not a diagnosis. Consult a doctor or qualified professional before making any health decision.

Your BMI

24.2

Normal weight (WHO) · Overweight (Asia-Pacific)

Underweight · Normal · Overweight · Obese

BMI Prime

0.97

Ponderal index

14.25

kg per m³

Healthy weight

53–72 kg

For your height (BMI 18.5–24.9)

BMI is a screening tool, not a diagnosis. For adults, the Asia-Pacific cutoffs (overweight ≥ 23) are often used in India because they better reflect body-fat-related risk. Consult a doctor for a full assessment.

How it works

BMI = weight (kg) ÷ height² (m). BMI Prime = BMI ÷ 25.

Example: 70 kg at 1.7 m → 70 ÷ (1.7 × 1.7) = 24.2 → Normal (WHO).

Last updated: September 2026

How this calculator is verified

Checked by Rahim Virani on 2 September 2026

BMI = weight(kg) / height(m)^2 verified against 70kg / 1.75m = 22.86
WHO and Asia-Pacific cut-off bands both applied; Asian band triggers below 23
Height accepts feet-inches and metres; unit mix-up raises an error instead of a wrong number

The full verification method is on our how we verify page. Found an error? Tell us and we will re-check it.

When to Use This Calculator

Use the BMI calculator whenever you need a quick weight check that doctors and insurers in India recognise. It is the standard first test in health check-up packages, before taking a life or health insurance policy, and during school and office fitness drives. Enter your height and weight to see whether you fall in the underweight, normal, overweight or obese range — the same categories hospitals quote on reports. Weight-loss programmes use it as a baseline, gym trainers track it alongside measurements, and families use it before planning a diet or a festive season where portions grow. Because BMI does not distinguish muscle from fat, read the result alongside waist size or body fat percentage if you train regularly.

How to Use This Calculator

Step 1: Pick the metric option so weight is entered in kilograms and height in centimetres.
Step 2: Enter your weight, for example 70, in the weight field.
Step 3: Enter your height, for example 170, in the height field and read the updated result.
Step 4: Read your BMI value, its WHO category, the Asia-Pacific category and the healthy weight range shown for your height.

Worked Example

A 30-year-old office worker in Mumbai who is 1.7 m tall and weighs 70 kg can enter both values in the metric fields. The calculator divides 70 by 1.7 squared and returns a BMI of 24.2. The WHO category is normal weight, which spans 18.5 to 24.9, but the Asia-Pacific cutoffs used widely in India classify 23 and above as overweight, so this person is in the raised-risk band. The healthy weight range shown for this height is about 53.5 to 72 kg.

Tips and Common Mistakes

•Tip 1: In India, check the Asia-Pacific category as well as the WHO one, because the 23 and 27.5 cutoffs flag risk earlier than the WHO thresholds.
•Tip 2: Measure height without shoes and weigh yourself in the morning before breakfast for the most consistent comparison over time.
•Tip 3: Use the healthy weight range output to set a practical target, since a change of a few kilograms can move the BMI category.
✗Mistake 1: Judging weight from BMI alone, because it does not distinguish muscle from fat, so a muscular person can show a high value.
✗Mistake 2: Entering height in metres as 1.7 when the field expects centimetres, which would return a wildly incorrect result.

Sources and References

Official sources are linked so you can confirm the current rate yourself. Check the linked page for the latest notification before relying on these figures.

Frequently Asked Questions

What is a good BMI?

For adults, the WHO considers a BMI of 18.5 to 24.9 as normal weight. Many health bodies in India use the Asia-Pacific cutoffs instead, where normal is 18.5 to 22.9 and overweight starts at 23.

Is BMI accurate?

BMI is a quick screening measure based on height and weight only. It does not measure body fat directly, so it can be misleading for very muscular people, athletes, older adults and during pregnancy.

Why does India use different BMI cutoffs?

Research shows that for the same BMI, people of Asian descent often have a higher percentage of body fat and higher health risk. That is why the Asia-Pacific cutoffs (overweight ≥ 23) are commonly recommended in India.

How do I calculate BMI?

Divide your weight in kilograms by your height in metres squared. For example, 70 kg and 1.7 m gives 70 ÷ (1.7 × 1.7) = 24.2.

What is BMI Prime?

BMI Prime is your BMI divided by 25, the top of the normal range. A value of 1 means you are at the boundary of overweight; above 1 is overweight, below 1 is within normal range.

You might also need

Related calculators from other categories

Science & Weather

Kinetic Energy Calculator

Calculate kinetic energy from mass and velocity in joules, kilojoules and calories. See how speed changes the energy.

Everyday

Bill Splitter

Split a bill between friends with tax and tip — tip on the subtotal or the total, and see exactly what each person owes.

Statistics

Confidence Interval Calculator

Build confidence intervals for a sample mean or proportion at 90%, 95% and 99% levels. Get the margin of error and interval bounds.