BMI Calculator
Calculate your Body Mass Index in seconds — with WHO categories and Asian-specific cutoffs.
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Adjust the inputs on the left to see your your bmi.
Introduction to the BMI Calculator
The BMI Calculator measures your body mass index, a screening number that relates weight to height. It is computed as weight in kilograms divided by the square of your height in metres. The result is matched to standard health ranges to flag underweight, healthy, overweight, or obese categories.
Indian adults use this tool for routine fitness checks, gym onboarding, pre-marital health screens, life insurance medicals, and lifestyle disease risk planning around diabetes and heart conditions. Related searches include weight to height ratio, body fat indicator, healthy weight check, and Asian BMI calculator.
You enter your height in cm or feet/inches and your weight in kg. The calculator returns your BMI value, the matching category by both WHO global cut-offs and Asian Indian cut-offs (ICMR), the ideal weight range for your height, and the kg to lose or gain to reach the healthy band.
Who Should Use This BMI Calculator
- Adults aged 20 to 60 doing a yearly health check before annual lab tests
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- Working professionals starting a gym, diet plan, or yoga routine in Bengaluru and Pune
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- Life insurance applicants checking BMI before LIC and HDFC Life medical screens
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- Parents tracking weight changes in teenage children pre-board exams
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- People with family history of diabetes wanting an early-warning health metric
Tips for BMI Tracking
Smart BMI Tracking Tips
- Use Asian Indian cut-offs: healthy is 18.5 to 22.9, overweight is 23 to 24.9, obese is 25 and above
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- Measure your weight first thing in the morning, after using the toilet, in light clothing
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- Track BMI once a fortnight, not daily, daily weight noise can be 1-2 kg from water alone
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- Combine BMI with waist size: men below 90 cm and women below 80 cm is considered safe
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- Athletes and bodybuilders often show high BMI but normal body fat, use body fat percentage too
Formula Explanation
Core BMI Formula
BMI = Weight in kg / (Height in m x Height in m)
Where:
- Weight = your current body weight in kilograms
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- Height = your standing height in metres (divide cm by 100)
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- Result = a number ranging roughly from 15 to 40 for adults
Example: For a 72 kg adult of height 170 cm, BMI = 72 / (1.70 x 1.70) = 72 / 2.89 = 24.91. This falls in the Asian Indian overweight band (23 to 24.9 is overweight, 25 plus is obese).
BMI Quick Reference Table
| Category (Asian) | BMI Range | Health Risk | Typical Action |
|---|---|---|---|
| Underweight | Below 18.5 | High | Increase calories |
| Healthy | 18.5 to 22.9 | Low | Maintain weight |
| Overweight | 23 to 24.9 | Moderate | Mild diet and exercise |
| Obese | 25 and above | High to severe | Structured weight plan |
Real-World Example
Example: Kavya's Pre-Marital Health Check
Meet Kavya, a 26-year-old marketing manager from Chennai, planning her wedding in 6 months. Her doctor has asked her to record BMI, BP, and blood sugar at the start of a pre-wedding wellness plan she is doing with her fitness coach.
Kavya weighs 68 kg and is 158 cm tall. She wants to know her current category and the kg she should drop in a steady, healthy way before the wedding, without crash dieting that doctors and the IDA strongly warn against.
Step 1: Kavya enters height 158 cm and weight 68 kg
Step 2: She selects the Asian Indian BMI range option
Step 3: She reads her current BMI and target healthy weight
Result: Her BMI is 27.24, which falls in the obese band by Asian Indian standards. Healthy weight for her height is between 46 and 57 kg, so she sets a target of 60 kg in 6 months, a 1.3 kg per month drop, well within safe limits for steady fat loss.
Frequently Asked Questions About BMI
This FAQ section answers the most common questions about BMI. Tap any question below for a clear, example-based answer.
Frequently asked questions
How does the BMI Calculator work?
Body Mass Index is your weight in kilograms divided by your height in metres squared. The formula is BMI = weight (kg) / height (m)^2. The BMI Calculator returns your score and the WHO category (underweight, normal, overweight, obese). For Indians and other South Asians, the calculator also shows the lower Asian cutoffs that the Ministry of Health recommends.
Are the Asian BMI cutoffs accurate for Indians?
Yes, the calculator uses the lower South Asian thresholds published by the WHO regional office and adopted by the Indian Ministry of Health and Family Welfare. Normal is 18.5-22.9, overweight is 23-24.9, and obese is 25+ (versus the standard 25 and 30 cutoffs for European populations). Indians develop metabolic risk at a lower BMI due to higher visceral fat at the same weight.
What inputs does the BMI Calculator need?
Enter your height (in centimetres or feet and inches) and weight (in kilograms or pounds). Optionally add age and gender for a more nuanced read-out. The calculator returns your BMI score, the WHO category, the Asian-cutoff category if applicable, and a position on a colour-coded gauge so you can see where you sit within or outside the healthy range.
What are the limitations of BMI for Indian bodies?
BMI does not distinguish muscle from fat, so athletes can score 'overweight' despite low body fat. It also misses waist-hip distribution, which matters more for cardiac risk. For Indians especially, waist circumference (under 90 cm for men, 80 cm for women per AIIMS guidelines) is a better single risk marker. Pair BMI with the Body Fat Calculator for a fuller picture.
Is the BMI Calculator free to use?
Yes, the BMI Calculator is completely free on AllSmartCalculators with no signup, ads inside the form, or login. Works on any phone or laptop browser. Bookmark it for monthly check-ins, before annual health checkups, when starting a fitness or weight programme, or whenever you want a quick objective number to track progress against.
What other calculators help with health tracking?
Pair the BMI Calculator with the Body Fat Calculator (for the muscle-versus-fat picture BMI misses), the BMR Calculator (for daily calorie needs at rest), and the Ideal Weight Calculator (for personalised target ranges). The Calorie Calculator helps plan weight-loss or weight-gain goals, and the Water Intake Calculator covers basic daily hydration.
Related calculators
BMR Calculator
Calculate your Basal Metabolic Rate — the calories your body burns at complete rest.
Calorie Calculator
Daily calorie needs to maintain, lose, or gain weight — based on your BMR and activity level.
Macro Calculator
Calculate protein, carbs, and fat ratios.
Body Fat %
Estimate body fat percentage.
Results from this calculator are estimates for informational use only — not financial, medical, or professional advice. Read our full disclaimer before acting on any number you see here.