What is BMI and why is it important?

BMI (Body Mass Index) measures body fat using height and weight. It helps assess healthy weight ranges and identify risks for overweight or obesity-related health issues.

How do I calculate my BMI?

To calculate your BMI, divide your weight in kilograms by your height in meters squared. For example, if you weigh 70 kg and are 1.75 m tall: BMI = 70 ÷ (1.75 × 1.75) = 22.9. You can also use our free online BMI calculator above for instant results without manual calculations.

What is a healthy BMI range?

A healthy BMI for adults is typically between 18.5 and 24.9. This range is associated with the lowest risk for weight-related health problems. However, BMI should be considered alongside other factors like age, gender, muscle mass, and overall health status.

BMI Calculator – Calculate Your BMI

Gender

👩Female

👨Male

Age (Optional)

Weight

Height

Results update automatically as you enter values.

BMI Prime:0.97

Range:18.5-24.9

24.2

Normal weight

Great! Your BMI is in the healthy range.

Learn more about normal weight

Information on this calculator is based on guidelines from WHO, CDC, and NHS.

These organizations provide evidence-based guidelines for BMI classification and health assessment.

Easily calculate your Body Mass Index (BMI) using our Advanced BMI Calculator. Input your height, weight, and optional details like gender, BMI Prime, or age for children and seniors. Instantly see your BMI value, category, and visual interpretation.

How to Use the Advanced BMI Calculator

Step-by-Step Instructions

1. Enter your height in centimeters (or feet/inches) 2. Enter your weight in kilograms (or pounds) 3. Select your gender (optional) 4. Optionally enter BMI Prime to compare with healthy range 5. Click 'Calculate' to get your BMI value and category

Tips for Accuracy

- Measure height without shoes and weight in light clothing - Use age or population-specific charts for children, seniors, or athletes - Interpret results with color-coded categories and examples

Advanced Calculator Inputs

Input Fields

- Height: number input (cm or ft/in) - Weight: number input (kg or lb) - Sex: dropdown (Male, Female, Other) optional - Age: optional for children/seniors - BMI Prime: optional numeric input comparing BMI to upper healthy limit

BMI Categories – Color-Coded Table

BMI Table

Use this color-coded table to quickly identify your BMI category and see practical examples.

Category	BMI Range	Example	Risk
Underweight	< 18.5	Male, 175 cm, 55 kg → BMI 18.0 → Underweight	Possible nutritional deficiency, lower energy levels
Normal weight	18.5 – 24.9	Female, 165 cm, 60 kg → BMI 22.0 → Normal	Low risk of weight-related health issues
Overweight	25 – 29.9	Male, 180 cm, 85 kg → BMI 26.2 → Overweight	Moderate risk for cardiovascular disease and diabetes
Obesity Class I (Moderate)	30 – 34.9	Female, 170 cm, 90 kg → BMI 31.1 → Obesity I	High risk for heart disease, type 2 diabetes
Obesity Class II (Severe)	35 – 39.9	Male, 175 cm, 110 kg → BMI 36.0 → Obesity II	Very high risk for cardiovascular disease, metabolic syndrome
Obesity Class III (Very Severe / Morbid)	≥ 40	Female, 165 cm, 110 kg → BMI 40.4 → Obesity III	Extremely high risk for serious health complications

Notes on Interpretation

- Categories follow WHO and CDC standards - BMI Prime compares your BMI to the upper limit of normal (1 = upper limit) - Adjust for children, athletes, and seniors using specialized charts

Examples of Calculator Results

Adult Example

- Male, 175 cm, 70 kg → BMI 22.9 → Normal

Child Example

- Female, 10 years, 32 kg, 140 cm → 60th percentile → Healthy

Athlete Example

- Male athlete, 180 cm, 85 kg → BMI 26.2 → Muscle mass adjusted → Normal

Senior Example

- Female, 70 years, 65 kg, 160 cm → BMI 25.4 → Normal (adjusted)

Tips for Accurate BMI Calculation

General Advice

- Use accurate measurements for height and weight - Consider combining BMI with other metrics like waist-to-hip ratio or body fat percentage - Recheck periodically to track changes over time

Homepage Mini-Widget Guidance

Mini Calculator Widget

- Place a compact version of the calculator on the homepage - Inputs: height, weight, optional gender - Display BMI value and color-coded category immediately - Go to BMI Calculator - Keep it responsive, fast-loading, and visually clean

BMI Calculator FAQ

How do I use the Advanced BMI Calculator?

Enter your height, weight, and optional details like gender, age, or BMI Prime. Click 'Calculate' to get your BMI value and category.

Is BMI accurate for all populations?

BMI is a screening tool. Adjustments may be needed for children, seniors, and athletes.

What is BMI Prime?

BMI Prime compares your BMI to the upper limit of normal. A value over 1 indicates overweight or obesity risk.

Can I use this calculator for children?

Yes, but use percentile charts according to age and gender for accurate interpretation.

Do I need a doctor to interpret my BMI?

BMI calculators are educational tools. Consult a healthcare professional for personalized advice.

How often should I check my BMI?

Periodically, especially when tracking lifestyle changes. Monthly or quarterly checks are recommended.

Medical References & Trusted Sources

World Health Organization (WHO) - Global authority on obesity classification and health standards. Our BMI categories follow WHO guidelines established in 1993.
Centers for Disease Control and Prevention (CDC) - Leading U.S. public health agency providing evidence-based guidelines for weight assessment and health promotion.
National Institutes of Health (NIH) - Primary U.S. agency for biomedical research, providing comprehensive health information and clinical guidelines.
Mayo Clinic - World-renowned medical institution providing patient-centered health information and evidence-based medical guidance.