BMI Calculator
Calculate your Body Mass Index (BMI) using metric or imperial units. Understand your BMI category and what it means for general health.
This tool is for informational purposes only and does not replace professional medical advice.
How it works
BMI (Body Mass Index) is calculated by dividing weight by height squared. It is widely used as a simple screening tool to classify weight status in adults.
Metric formula: BMI = weight (kg) ÷ height (m)²
Imperial formula: BMI = (weight (lb) ÷ height (in)²) × 703
How to interpret results:
- Underweight may indicate insufficient body weight
- Normal range is generally associated with lower health risk
- Overweight and obesity are associated with increased risk of certain conditions
BMI does not measure body fat directly. It should be used together with other indicators such as waist circumference, lifestyle factors, and clinical evaluation.
Examples
- General health check: A person enters height and weight to quickly assess if they are within a normal BMI range.
- Fitness tracking: Monitor BMI changes over time when adjusting diet or exercise.
- Weight management planning: Identify whether weight loss or gain may be appropriate.
Example calculations:
- 170 cm, 65 kg → BMI = 65 ÷ (1.70²) = 22.49 (Normal)
- 180 cm, 90 kg → BMI = 90 ÷ (1.80²) = 27.78 (Overweight)
- 70 in, 160 lb → BMI = (160 ÷ 70²) × 703 = 22.96 (Normal)
When to use this tool
This tool is designed for quick, practical tasks such as everyday calculations, data formatting, or simple conversions. It is best used when you need fast results without installing software or using complex tools.
When to use
- Quick checks or one-time calculations
- Validating or converting data before using it elsewhere
- Simple tasks that do not require advanced software
When not to use
- Critical financial, legal, or medical decisions
- Large-scale or automated processing
- Situations requiring guaranteed precision beyond basic validation
Always review results before using them in important contexts.
About this tool
This tool helps you perform quick utility operations directly in your browser. It runs entirely in your browser without sending data to a server.
You can use this tool when handling simple tasks without installing additional software. The results should be interpreted as a processed output based on your input data.
FAQ
- Is BMI accurate?
BMI is a screening tool based on height and weight. It does not directly measure body fat, muscle mass, or individual health risk.
- Is this BMI calculator for adults only?
Yes. The BMI categories shown here are for adults. Children and teens require age- and sex-specific BMI percentiles.
- Does BMI consider muscle?
No. Individuals with higher muscle mass may have a higher BMI without having excess body fat.
- Which BMI categories are used?
Standard adult BMI categories: underweight (<18.5), normal (18.5–24.9), overweight (25–29.9), obesity (≥30).
- What does my BMI result mean?
Your BMI category indicates general weight status. It should be interpreted alongside other health indicators such as waist circumference, body fat percentage, and medical advice.
- Is my data stored?
No. All calculations run locally in your browser and no personal data is uploaded or stored.