🧮 BMI Calculator
Body mass index (BMI) is the most widely used method for assessing weight. Calculate your BMI in seconds.
📐 BMI Formula
BMI = weight (kg) / height (m)²
Example: 70 kg and 1,75 m = 70/(1.75×1.75) = 22.9
📊 BMI Statistics and Facts
Global Statistics
About 39% of the world's adults are overweight (BMI ≥ 25), and 13% have obesity (BMI ≥ 30). In Lithuania, about 57% of the population is overweight.
Historical Fact
The BMI formula was created in 1832 by Belgian mathematician Adolphe Quetelet. Initially, it was intended for population studies, not individual assessment.
BMI Limitations
BMI does not distinguish muscle from fat — professional athletes often have a high BMI due to muscle mass. It is also not suitable for children, pregnant women, and the elderly.
💡 Practical Tips
- Measure Regularly, but Not Every Day — weigh yourself once a week at the same time (preferably in the morning, on an empty stomach). Daily fluctuations can reach 1–2 kg.
- Combine with Other Indicators — along with BMI, measure waist circumference. For men >94 cm, for women >80 cm indicates increased health risk.
- Use as a Reference Point — BMI is a good starting reference, but body fat percentage, physical activity, and nutrition quality are more important for health assessment.
- Healthy BMI Range — the optimal range for health is BMI 20–23. Below 18.5 and above 30, the risk of health problems increases significantly.
What the BMI Result Shows
Body mass index (BMI) shows the ratio of weight to height, so it is a quick way to assess whether your weight falls into a particular category. However, BMI does not measure body composition: it does not tell you how much muscle versus fat you have. Therefore, the result should be used as an initial guide, not as a final verdict.
📏 Weight Categories by BMI
- Less than 18,5 — underweight; may pose a risk if associated with inadequate nutrition.
- 18,5–24,9 — normal weight range.
- 25–29,9 — overweight.
- 30 and above — obesity, which can be further classified by degree.
These thresholds are general and apply to adults, not children, pregnant women, or athletes.
⚠️ When BMI Is Not Suitable
- For People With High Muscle Mass — athletes’ BMI can be high even with low body fat (see body fat).
- For Children and Adolescents — age- and sex-specific tables apply to them.
- For Pregnant and Breastfeeding Women — weight changes here are natural.
- For the Elderly — due to muscle loss, BMI may underestimate risk.
🙋 Frequently Asked Questions
Can I Rely on BMI Alone? No — combine it with waist circumference and body composition.
What BMI Is Considered Optimal? The most commonly cited range is 18,5–24,9, but an individual target depends on many factors.
How Does BMI Differ From Ideal Weight? BMI assesses the weight-to-height ratio, while ideal weight calculator provides a specific weight point based on formulas.
Should I See a Doctor? If your BMI is very low or very high, or if you have other health concerns, it is worth consulting a specialist.