Free health calculators verified against WHO, NIH and other authoritative medical sources. Every result includes educational context and a disclaimer.
These are the four numbers your doctor checks first. Know them before your appointment.
| Measurement | Healthy range | Tool to check |
|---|---|---|
| BMI | 18.5 – 24.9 (WHO) | 18.5 – 22.9 (South Asia) | BMI Calculator |
| Waist (women) | Below 80 cm (low risk per WHO) | Tape measure |
| Waist (men) | Below 94 cm (low risk per WHO) | Tape measure |
| Daily calories | Varies by age, gender, activity level | Calorie Calculator |
The three tools on this page describe your body from different angles, and they are most useful in combination. The BMI calculator is the quick screen: weight relative to height, classified against WHO guidelines, including the lower South Asian thresholds recommended for Indian populations. It takes ten seconds and tells you whether your weight sits in a range associated with higher health risk.
BMI cannot tell muscle from fat, though — which is where the body fat calculator comes in. Using the US Navy circumference method, it estimates your body fat percentage from tape measurements of your waist, neck and (for women) hips. A muscular person with a "high" BMI and a low body fat percentage has little to worry about; a normal-BMI person with high body fat — a pattern research shows is common in South Asian populations — benefits from knowing it early.
Once you know where you stand, the calorie calculator tells you what to do about it. Using the Mifflin-St Jeor equation, it estimates the daily calories that maintain your current weight, and the adjusted targets for gradual, sustainable weight loss or gain. A sensible monthly routine: track your weight and waist measurement, recalculate your calorie needs when your weight changes by more than a few kilograms, and watch the trend rather than any single reading. All three tools run entirely in your browser and none of your measurements are stored or transmitted.