Quick answer: BMI = weight (kg) ÷ height² (m²). Per the World Health Organisation, an adult BMI of 18.5–24.9 is considered a healthy range, 25 and above is classified as overweight, and 30 and above as obese (WHO obesity & overweight fact sheet). Enter your details below for your personalised result.
Formula and category thresholds sourced directly from WHO guidance (linked above). Last reviewed September 2026. This tool is for general information only and doesn't replace medical advice — see a doctor for a personal health assessment.
⚕️ Calculate Your BMI Main Tool
Enter your height and weight above to calculate your BMI instantly. Add age and sex for body fat and calorie estimates.
⚖️ Ideal Weight Range Details
Enter your height, weight, age, and sex in Section 1 to see your healthy weight range.
🔥 Body Fat Estimate Formula
Enter your height, weight, age, and sex in Section 1 to estimate body fat percentage.
🍎 Daily Calorie Needs (TDEE, Mifflin-St Jeor) Estimate
Enter your details in Section 1 to estimate your daily calorie needs.
💡 Personalised Health Tips
Calculate your BMI above to receive personalised health tips.
📊 BMI Reference Table WHO Scale
| Category | BMI Range | Health Risk |
|---|---|---|
| Underweight | < 18.5 | Malnutrition risk |
| Normal weight | 18.5 – 24.9 | Low |
| Overweight | 25.0 – 29.9 | Increased |
| Obese Class I | 30.0 – 34.9 | High |
| Obese Class II | 35.0 – 39.9 | Very high |
| Obese Class III | ≥ 40.0 | Extremely high |
📄 Download BMI Report PDF Export
Calculate your BMI above to generate and download your personalised BMI report.
Related Tools
How Is BMI Calculated?
BMI (body mass index) is your weight in kilograms divided by your height in metres squared. Someone 170 cm tall weighing 70 kg has a BMI of 70 ÷ 1.70² = 24.2, which is in the healthy range. In pounds and inches, use 703 × weight ÷ height². For adults, the WHO healthy range is 18.5 to 24.9.
BMI Formula
Metric: BMI = weight (kg) ÷ height (m)². Imperial: BMI = 703 × weight (lb) ÷ height (in)². Example: 5 ft 7 in (67 in) and 154 lb gives 703 × 154 ÷ 67² = 24.1.
Adult BMI Categories (WHO)
| BMI | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 – 24.9 | Healthy weight |
| 25.0 – 29.9 | Overweight |
| 30.0 – 34.9 | Obese class I |
| 35.0 – 39.9 | Obese class II |
| 40 and above | Obese class III |
BMI Chart: Healthy Weight for Your Height
The same chart applies to men and women aged 18 and over. Weights are for a BMI of 18.5 to 24.9.
| Height | Healthy weight (kg) | Height | Healthy weight (lb) |
|---|---|---|---|
| 150 cm | 41.6 – 56.0 | 5 ft 0 in | 95 – 128 |
| 160 cm | 47.4 – 63.7 | 5 ft 4 in | 108 – 145 |
| 165 cm | 50.4 – 67.8 | 5 ft 6 in | 115 – 154 |
| 170 cm | 53.5 – 72.0 | 5 ft 8 in | 122 – 164 |
| 175 cm | 56.7 – 76.3 | 5 ft 10 in | 129 – 174 |
| 180 cm | 59.9 – 80.7 | 6 ft 0 in | 136 – 184 |
| 190 cm | 66.8 – 89.9 | 6 ft 2 in | 144 – 194 |
Is BMI Different for Men and Women?
No. The formula and the categories are the same for both. At the same BMI, women usually carry more body fat than men, so the calculator asks for your sex only for the body fat and calorie estimates, not for the BMI itself.
BMI for Asian Adults
A 2004 WHO expert consultation found that many Asian populations have higher health risks at lower BMIs, and suggested extra action points: 23 for increased risk and 27.5 for high risk. Several countries use these lower cut-offs. The calculator shows the standard WHO categories, so compare your number with these points yourself.
What the Other Sections Estimate
- Healthy weight range for your height, from BMI 18.5 to 24.9, with a midpoint at BMI 22.
- Body fat using the Deurenberg formula, which adds age and sex to BMI. It's an estimate, not a measurement.
- Daily calories using the Mifflin-St Jeor equation and your activity level.
What BMI Doesn't Tell You
BMI can't separate muscle from fat or show where fat is stored, so a muscular athlete may read as overweight. Waist size adds useful information: a waist under half your height is linked with lower risk. BMI categories are for adults only; children and teens are assessed with age- and sex-specific growth charts. For advice about your own health, talk to a doctor.
Read is BMI accurate? and how to calculate BMI and what your score means. Track weight and habits over time with the fitness planner, or see how many weeks you've lived with the life in weeks calculator.
How to Use the BMI Calculator
- Choose metric (kg and cm) or imperial (lb, feet and inches).
- Enter your height and weight.
- Add your age, sex and activity level for the calorie and body-fat estimates.
- Read your BMI and category, ideal weight range, body-fat estimate and daily calories; download a PDF report if you like.
Who Uses the BMI Calculator?
- Health check-ins: track BMI alongside waist size over time.
- Weight goals: see the healthy weight range for your height.
- Fitness plans: estimate daily calories from your activity level.
How the BMI Calculator Saves You Time
BMI, ideal weight, body fat and calorie needs each use a different formula. One form gives all of them together.
Frequently Asked Questions
How do I calculate my BMI?
What is a healthy BMI for adults?
How much should I weigh for my height?
Is there a separate BMI chart for men and women?
Is BMI accurate for athletes and muscular people?
What BMI is healthy for Asian adults?
Does this BMI calculator save my data?
Last updated: September 2026