BMI calculator: check your body mass index
Enter your weight and height: we'll tell you your BMI, which WHO category you're in and what weight is healthy for your height. Further down you'll find the full chart.
It's an estimate, not a diagnosis. It doesn't replace a professional. It doesn't apply during pregnancy or to anyone under 18.
Take it to your plan. Mobbe uses your weight and height to build your routine and, with PRO, your meals.
WHO BMI chart
The ranges are the same for women and men from age 18.
| BMI | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 to 24.9 | Healthy weight |
| 25 to 29.9 | Overweight |
| 30 to 34.9 | Obesity class 1 |
| 35 to 39.9 | Obesity class 2 |
| 40 or more | Obesity class 3 |
Healthy weight for your height
| Height | Healthy weight |
|---|---|
| 4 ft 10 in | 89 to 119 lb |
| 5 ft 0 in | 95 to 127 lb |
| 5 ft 2 in | 101 to 136 lb |
| 5 ft 4 in | 108 to 145 lb |
| 5 ft 6 in | 115 to 154 lb |
| 5 ft 8 in | 122 to 164 lb |
| 5 ft 10 in | 129 to 173 lb |
| 6 ft 0 in | 137 to 183 lb |
| 6 ft 2 in | 144 to 194 lb |
| 6 ft 4 in | 152 to 204 lb |
| 6 ft 6 in | 160 to 215 lb |
To also see what the formulas give for women and men, use the ideal weight calculator.
How BMI is calculated
The WHO formula, with the worked example, and what BMI doesn't tell you.
- Step 1
Weight divided by height squared
At 82 kg and 1.78 m: 82 ÷ (1.78 × 1.78) = 25.9. In pounds and inches, multiply by 703: 703 × 181 ÷ (70 × 70) = 26.0.
BMI = weight (kg) ÷ height (m)²WHO, 2000. - Step 2
Placed in the WHO ranges
From 18.5 to 24.9 is a healthy weight. The healthy range for your height comes from multiplying 18.5 and 24.9 by your height squared.
healthy weight = 18.5 to 24.9 × height (m)²WHO, 2000. - Step 3
What it doesn't measure
It doesn't tell muscle from fat or show where the fat is. With a lot of muscle it reads higher than it should.
Romero-Corral, 2008. - Step 4
How Mobbe uses it
With a BMI of 27.5 or more, protein is calculated on the weight you'd have at a BMI of 27.5. With a BMI under 20, Mobbe doesn't suggest losing weight.
Weijs, 2025; GLIM, 2019.
Sources
- World Health Organization. Obesity: preventing and managing the global epidemic. Report of a WHO consultation. WHO Technical Report Series 894. Geneva: WHO; 2000.
- Romero-Corral A, Somers VK, Sierra-Johnson J, et al. Accuracy of body mass index in diagnosing obesity in the adult general population. Int J Obes. 2008;32(6):959-966. doi:10.1038/ijo.2008.11
- Weijs PJM. Protein requirement in obesity. Curr Opin Clin Nutr Metab Care. 2025;28(1):27-32.
- Cederholm T, Jensen GL, Correia MITD, et al. GLIM criteria for the diagnosis of malnutrition. J Cachexia Sarcopenia Muscle. 2019;10(1):207-217. doi:10.1002/jcsm.12383
Frequently asked questions
What is BMI?
It's the body mass index: your weight divided by your height squared. The WHO uses it to classify adults' weight.
Is it the same for women and men?
Yes. The formula and the ranges are the same from age 18.
What is a normal BMI?
From 18.5 to 24.9.
Does it work if I lift weights?
It works as a reference, but muscle can push it into overweight. Also check your waist and how your strength changes. Estimate your body fat percentage.
Does it work for children and teens?
No. For anyone under 18, charts by age and sex are used.
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Mobbe builds your plan with these numbers
Download Mobbe and answer a few questions: with your weight and height it builds your routine and, with PRO, your meal plan with grams of each food.
