Calculate Your BMI

Enter your height and weight to find out your Body Mass Index (BMI). Our interactive visual guide will help you understand where you stand on the health spectrum.

BMI Calculator

BMI Calculator

Use this calculator to check your body mass index (BMI) and find out if you're at a healthy weight.

Your BMI is

22.9

Healthy Weight

Healthy BMI range: 18.5 kg/m² - 25 kg/m²

Body Proportions Map

Compare your height and body mass index against a 6ft (182.88cm) reference.

Enter your details to see the visual mapping.
BMI =
mass (kg)height² (m)

Your Fitness Journey

Whether you're looking to build muscle, increase flexibility, or improve cardiovascular health, everything starts with understanding your body.

Fitness
Cardio

Elevate your heart rate

Yoga
Flexibility

Find your balance

Weights
Strength

Build resilience

Nutrition
Nutrition

Fuel your body right

Proper nutrition is the foundation of any fitness goal. Understand your macros and make every calorie count.

✦ The Core Metric

What is BMI?

Body Mass Index (BMI) is a foundational ratio of weight to height used to estimate whether your body size falls within a healthy range. It’s globally recognized as a rapid screening tool for assessing overall health risks, serving as the starting line for your fitness journey.

Adult Categories

Estimated based on global population of ~8.4 Billion (2026)

UnderweightBMI < 18.5
2.0%~168M
HealthyUnhealthy
Normal / HealthyBMI 18.5 – 24.9
25.0%~2.1B
HealthyUnhealthy
OverweightBMI 25.0 – 29.9
31.7%~2.66B
HealthyUnhealthy
ObeseBMI ≥ 30
40.3%~3.39B
HealthyUnhealthy

Children & Teens

Aged 2-20 years old, CDC uses percentiles:

Underweight: < 5%
Healthy weight: 5% – 85%
At risk: 85% – 95%
Overweight: > 95%
!

Limitations of BMI

  • Doesn't distinguish fat from muscle mass.
  • Athletes may appear “overweight”.
  • Older adults may have higher fat levels even at a “normal” BMI.
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Understanding Health Risks

A BMI outside the healthy range can significantly impact your long-term wellbeing. Here's a look at the global statistics and most common issues.

Overweight Risks

1+ BillionGlobally Affected (WHO)
Heart Disease

Heart Disease & Stroke

Excess weight forces the heart to work harder. Cardiovascular diseases take ~17.9 million lives annually worldwide.

Type 2 Diabetes

Type 2 Diabetes

Over 422 million people have diabetes. Obesity drastically reduces insulin sensitivity, spiking blood sugar.

Joint Pain & Sleep Apnea

Joint Pain & Sleep Apnea

Extra load degrades cartilage (osteoarthritis) while excess neck tissue can obstruct breathing during sleep.

Underweight Risks

462 MillionGlobally Affected (WHO)
Malnutrition

Malnutrition & Deficiencies

A lack of essential nutrients leads to fatigue, anemia (iron deficiency), and stunted tissue repair.

Weakened Immune System

Weakened Immune System

Without adequate fuel and vitamins, the body struggles to fight off viruses, leading to frequent illnesses.

Osteoporosis

Osteoporosis

Low body weight and lack of calcium/vitamin D severely diminishes bone density, increasing fracture risk.

The Blueprint

5 Steps to Overcome &
Reclaim Your Health

Whether you need to lose excess weight or build a stronger, well-nourished frame, the fundamentals of recovery remain the same.

Assess and Track
01

Assess & Track

Don't guess. Regularly use calculators and track your intake to understand your baseline metrics.

Nutrition
02

Nutrition

Focus on a caloric deficit for fat loss, or a nutrient-dense caloric surplus for healthy weight gain.

Movement
03

Movement

Cardio improves heart health; strength training builds bone density and muscle mass.

Recovery
04

Recovery

High-quality sleep is crucial. It regulates hunger hormones and repairs damaged tissues.

Consistency
05

Consistency

Avoid crash diets. Sustainable, long-term habits are the only way to permanent changes.

Additional Measures

Beyond standard BMI, other indices can provide additional context about your body composition.

BMI Prime

What it is: A simple ratio comparing your BMI to the maximum "normal" limit (25).

Why it matters: It instantly tells you how far off you are from a healthy range.

The Golden Rule: Keep your score between 0.74 and 1.0. Anything over 1.0 means overweight.

Formula

BMI Prime = BMI25
ClassificationBMIBMI Prime
Severe Thinness< 16< 0.64
Moderate Thinness16 - 170.64 - 0.68
Mild Thinness17 - 18.50.68 - 0.74
Normal18.5 - 250.74 - 1
Overweight25 - 301 - 1.2
Obese Class I30 - 351.2 - 1.4
Obese Class II35 - 401.4 - 1.6
Obese Class III> 40> 1.6

Ponderal Index

What it is

Similar to BMI, but it cubes your height (heightÂł) instead of squaring it.

The BMI Flaw

Regular BMI is often inaccurate for people who are exceptionally tall or short.

The Solution

Ponderal Index fixes this distortion, providing a much more reliable metric for extreme heights.

USC Units

PI =height (in)³√mass (lbs)=70³√160= 12.9

SI Metric Units

PI =mass (kg)heightÂł (m)=72.571.778Âł= 12.9
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Optimized BMI & Fitness FAQ

Find answers to the most commonly asked questions regarding body mass index, accuracy, and fitness.

General BMI

How is BMI calculated?
A BMI calculator uses your height and weight to estimate body fat. To calculate BMI, divide your weight in kilograms by your height in meters squared (kg/m²).
How is BMI interpreted for adults?
For adults over 20, BMI ranges are standardized regardless of age or gender. A healthy BMI is between 18.5 and 24.9, while 25 to 29.9 indicates overweight, and 30 or above indicates obesity.
Why use BMI?
BMI is widely used because it's a simple, inexpensive, and non-invasive screening tool. While not a diagnostic tool for body fat, it reliably identifies potential weight-related health risks.
How is BMI used to assess obesity?
Medical professionals use a BMI calculator as a primary screening tool for obesity. A BMI of 30 or higher typically flags obesity, prompting further health assessments.
What are the health consequences of obesity for adults?
Adults with a BMI in the obese range face higher risks for conditions like type 2 diabetes, high blood pressure, and cardiovascular diseases. Maintaining a healthy body mass index reduces these risks.
Is BMI a good indicator of body fat?
Is BMI accurate for everyone? Generally yes, but it doesn't directly measure body fat. It cannot distinguish between muscle mass and fat, which is why a BMI chart should be used alongside other health markers.
What are trends in obesity worldwide?
Global obesity rates have nearly tripled since 1975, affecting billions of adults and children. Regular use of a BMI calculator helps populations track and manage this growing health epidemic.
If an athlete has a high BMI, are they overweight?
No, a high BMI doesn't always mean overweight. Because muscle weighs more than fat, athletes often fall into the 'overweight' BMI ranges despite having very low body fat percentages.

Children & Teens

How is BMI calculated for children and teens?
A child BMI calculator uses the exact same weight and height formula as adults. However, the results are interpreted using age- and sex-specific percentiles rather than fixed BMI ranges.
How do I interpret BMI percentiles for children and teens?
A teen BMI calculator plots the result on a growth chart. A healthy BMI falls between the 5th and 85th percentiles for their specific age and gender.
Should BMI be interpreted the same way for children and adults?
No, because children are still growing and boys and girls develop at different rates. A BMI chart for children uses percentiles, whereas adult charts use static numerical thresholds.
What are the health consequences of obesity for children and teens?
Children with high BMI percentiles are at greater risk for asthma, sleep apnea, bone and joint problems, and type 2 diabetes. Early intervention can prevent these issues from continuing into adulthood.