BMI Prime: 0
Ponderal Index: 0 kg/m³
:
Curious about your weight status? Our BMI Calculator quickly evaluates your Body Mass Index (BMI) based on your height, weight, and age, offering insights into whether you’re in a healthy range. Perfect for fitness tracking, health monitoring, or weight management, it also includes BMI Prime and Ponderal Index for a deeper health perspective.
A BMI Calculator measures your Body Mass Index, a simple ratio of weight to height, to classify your weight status (underweight, healthy, overweight, or obese). It also provides:
While BMI doesn’t directly measure body fat, it’s a widely used screening tool endorsed by the World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC).
The calculator uses your weight and height to compute BMI, then categorizes it based on WHO standards. It also calculates BMI Prime (BMI ÷ 25) and Ponderal Index (weight ÷ height³) for a fuller picture.
Example:
Person: 70 kg, 1.75 m
BMI: 70 ÷ (1.75)² ≈ 22.9 (Healthy)
BMI Prime: 22.9 ÷ 25 ≈ 0.92 (Healthy)
Ponderal Index: 70 ÷ (1.75)³ ≈ 13.1 kg/m³
Formulas:
Metric BMI: Weight (kg) ÷ Height² (m)
Imperial BMI: 703 × Weight (lbs) ÷ Height² (in)
BMI Prime: BMI ÷ 25
Ponderal Index (Metric): Weight (kg) ÷ Height³ (m)
Ponderal Index (Imperial): Height (in) ÷ ∛Weight (lbs)
You’ll get:
✔ Your BMI and weight category
✔ BMI Prime and Ponderal Index
✔ Health insights based on WHO/CDC guidelines
Q1: How accurate is BMI?
✅ BMI is a reliable screening tool but doesn’t measure body fat directly. Use it with other health metrics.
Q2: What is BMI Prime?
✅ It’s your BMI divided by 25, showing how your weight compares to the healthy range.
Q3: Why use the Ponderal Index?
✅ It’s better for very tall or short people, as it accounts for height cubed.
Q4: Is BMI different for kids?
✅ Yes, kids’ BMI uses percentiles to account for growth and age.
Q5: Can BMI misclassify athletes?
✅ Yes, high muscle mass can result in a higher BMI, even if body fat is low.
Body Mass Index (BMI) is a quick way to assess weight relative to height, categorizing you as underweight, healthy, overweight, or obese. Developed in the 1830s by Adolphe Quetelet, it’s a cornerstone of health screening, endorsed by WHO and CDC. While simple, it’s not perfect—it doesn’t measure body fat or account for muscle mass, age, or sex differences.
| Category | BMI (kg/m²) | BMI Prime |
|---|---|---|
| Severe Underweight | <16 | <0.64 |
| Moderate Underweight | 16–17 | 0.64–0.68 |
| Mild Underweight | 17–18.5 | 0.68–0.74 |
| Healthy Weight | 18.5–25 | 0.74–1 |
| Pre-Obese | 25–30 | 1–1.2 |
| Obese Level 1 | 30–35 | 1.2–1.4 |
| Obese Level 2 | 35–40 | 1.4–1.6 |
| Obese Level 3 | >40 | >1.6 |
For children, BMI is interpreted using percentiles to account for growth and development, per CDC guidelines:
| Category | Percentile Range |
|---|---|
| Underweight | <5th |
| Healthy Weight | 5th–85th |
| At Risk of Overweight | 85th–95th |
| Overweight | >95th |
Excess weight (BMI ≥ 25) increases the risk of:
Being underweight (BMI < 18.5) can lead to:
BMI is a starting point but has limitations:
Pair BMI with other metrics like waist circumference or body fat percentage for a fuller picture.
BMI Prime divides your BMI by 25 (healthy cutoff). A value of 0.74–1 is healthy, >1 suggests overweight, and >1.2 indicates obesity.
Ponderal Index (weight ÷ height³) is more accurate for very tall or short individuals, as it accounts for body proportions better than BMI.
Source: Synthesized from WHO and CDC guidelines, 2023.
Our Free BMI Calculator empowers you to monitor your weight status and make informed health decisions. With BMI, BMI Prime, and Ponderal Index, you get a comprehensive view to support fitness, weight management, and wellness.
🚀 Check your BMI now!
This BMI Calculator content is independently researched and authored by me, based on WHO and CDC guidelines and health science principles.
Body Mass Index (BMI) is a measure that uses height and weight to determine if your weight is in a healthy range.
Formula: BMI = weight (kg) / height (m)²