Height Calculator – Convert Height Units & Health Metrics
Convert height between centimeters, meters, feet, and inches, and calculate BMI and ideal weight ranges for health assessment.
Enter your height and optionally your age, gender, and weight to get complete unit conversions and health metric calculations.
Height Calculator – Convert Height Units & Health Metrics
Convert height between centimeters, meters, feet, and inches, and calculate BMI and ideal weight ranges for health assessment.
About the Height Calculator
Height is one of the most fundamental anthropometric measurements in medicine, sports science, nutrition, and everyday life. Whether you are converting between measurement systems, calculating BMI, assessing growth, or determining clothing and furniture sizes, accurate height measurement and reliable unit conversion are essential. This calculator provides instant conversion between all common height units and adds contextual health metrics when additional information is provided.
The four common height units in global use are centimeters (cm), meters (m), feet (ft), and inches (in). The metric system — used throughout most of the world — measures height in centimeters or meters. The imperial system — used primarily in the United States — measures height in feet and inches. One foot equals exactly 30.48 centimeters; one inch equals 2.54 centimeters. A person who is 175 cm tall is approximately 5 feet 9 inches (5'9") in the imperial system.
Conversion formulas are straightforward: to convert cm to inches, divide by 2.54; to convert inches to cm, multiply by 2.54; to get feet and inches from cm, first divide by 30.48 to get the feet component (take the integer part), then multiply the remainder by 12 to get inches.
Body Mass Index (BMI) is calculated when both height and weight are provided. BMI = weight (kg) / height² (m²). The World Health Organization (WHO) defines BMI categories as follows: underweight is BMI below 18.5, normal weight is 18.5–24.9, overweight is 25–29.9, and obese is 30 or above. BMI is a useful population-level screening tool but has well-known limitations — it does not distinguish between fat and lean muscle mass, and the same BMI can represent very different body compositions in different individuals.
Ideal body weight formulas provide another reference point. The Devine formula (1974) remains widely used in clinical practice, particularly for drug dosing: for men, IBW (kg) = 50 + 2.3 × (height in inches − 60); for women, IBW (kg) = 45.5 + 2.3 × (height in inches − 60). The Robinson formula and Miller formula provide slightly different estimates. This calculator presents a range based on a normal BMI (18.5–24.9) applied to the entered height, which is the most straightforward reference range for a healthy body weight.
Height can also be used as a proxy for frame size, nutritional status, and developmental stage. In pediatric medicine, height tracking on standardized growth charts is one of the primary tools for identifying growth hormone deficiency, malnutrition, chronic disease, or skeletal dysplasia. In adults, height loss of more than 2–3 cm may indicate vertebral compression fractures or osteoporosis and warrants investigation.
This calculator is designed for informational and educational purposes. BMI and ideal weight calculations are screening tools and do not constitute a diagnosis or medical advice. Consult a healthcare provider for personalized assessment of weight and height in the context of your overall health.
Height Calculator Examples
These examples demonstrate common height conversions and health metric calculations across different input units.
| Input | Converted Height | Notes |
|---|---|---|
| 175 cm, Male, Age 30, Weight 75 kg | 5 ft 8.9 in / 1.75 m | Average adult male height. BMI = 24.5 (Normal weight). Ideal weight range: 56.7–76.3 kg. |
| 162 cm, Female, Age 28, Weight 60 kg | 5 ft 3.8 in / 1.62 m | Average adult female height. BMI = 22.9 (Normal weight). Ideal weight range: 48.6–64.1 kg. |
| 6 ft (72 inches) | 182.88 cm / 1.83 m | Simple unit conversion from feet to metric. Above average height for most global populations. |
| 5 ft 10 in (70 inches) | 177.8 cm / 1.78 m | Common height for adult males in North America. Converts to 177.8 cm in metric system. |
How to Use the Height Calculator
- Enter your height value and select the unit (cm, m, ft, or in) from the dropdown menu.
- Optionally enter your age in years — this enables age-specific context in the results.
- Optionally select your gender for sex-specific ideal weight calculations.
- Optionally enter your weight in kilograms to enable BMI calculation and ideal weight comparison.
- Click Calculate to see the complete unit conversion table and any available health metrics.
Height Calculator FAQ
How do I convert height from feet and inches to centimeters?
Multiply the number of feet by 30.48, then multiply the number of remaining inches by 2.54, and add the two results together. For example, 5 feet 9 inches = (5 × 30.48) + (9 × 2.54) = 152.4 + 22.86 = 175.26 cm. This calculator does the conversion automatically for any input unit.
What is the average height for men and women?
Average height varies significantly by country and region. The global average height for adult men is approximately 171 cm (5'7"), and for adult women approximately 159 cm (5'3"). The Netherlands has the tallest average male height at around 182 cm, while some South and Southeast Asian populations average closer to 160–165 cm for men. Heights in most countries have been gradually increasing over the past century due to improved nutrition.
What is a healthy height-to-weight ratio?
A commonly used guideline is the BMI range of 18.5–24.9, which corresponds to a specific weight range for each height. For a person 175 cm tall, this translates to approximately 56–77 kg. However, BMI has limitations — it does not account for muscle mass, bone density, or body fat distribution. Waist circumference, waist-to-height ratio, and body composition measurements provide additional context.
How accurate is BMI as a health indicator?
BMI is a useful population-level screening tool and correlates reasonably well with body fat percentage in large groups. However, it has recognized limitations: muscular individuals may have a high BMI despite low body fat; elderly individuals may have a normal BMI despite high body fat due to muscle loss. BMI also does not capture where fat is stored, which matters for cardiovascular risk — central (abdominal) fat is more harmful than peripheral fat.
Does height affect health outcomes?
Research suggests associations between height and several health outcomes. Taller individuals have lower risk of coronary heart disease (partly due to larger coronary artery diameter) but may have slightly higher risk of certain cancers due to greater cell count. Short stature in childhood, if not familial, can be a sign of growth hormone deficiency, chronic disease, or nutritional issues requiring medical evaluation.
How is ideal body weight calculated?
Several formulas exist for ideal body weight (IBW). The most widely used in clinical settings is the Devine formula: for men, IBW = 50 kg + 2.3 kg per inch over 5 feet; for women, IBW = 45.5 kg + 2.3 kg per inch over 5 feet. This calculator presents an ideal weight range based on the WHO normal BMI range (18.5–24.9) applied to the entered height, which gives a practical reference interval rather than a single target.