Male
Female
Select your gender for more accurate calculation.
Your Estimated Body Fat Percentage:–.–%
–.–BMI
–.–Lean Mass (kg)
–.–Fat Mass (kg)
Body fat percentage is estimated using a common formula that combines BMI, age, and gender.
It's an approximation and not a direct measurement.
Body Fat Percentage Chart
Comparison of estimated Body Fat % vs. Age for different genders at average BMI.
Body Fat Percentage Reference Ranges
Category
Men (%)
Women (%)
Essential Fat
2-5%
10-13%
Athletes
6-13%
14-20%
Fitness
14-17%
21-24%
Average
18-24%
25-31%
Obese
25%+
32%+
What is Body Fat Percentage?
Body fat percentage represents the proportion of your total body weight that is fat. This is a more insightful metric for assessing health and fitness than simple weight or BMI alone. It considers both essential fat (needed for bodily functions like hormone regulation and insulation) and storage fat (accumulated energy). Understanding your body fat percentage helps you gauge your fitness level, identify potential health risks associated with being overweight or underweight, and set realistic health goals.
Who should use body fat percentage calculations? Anyone interested in their overall health and fitness, athletes looking to optimize performance, individuals managing weight for health reasons, and those curious about their body composition. It's particularly useful for differentiating between muscle mass and fat mass, as weight alone doesn't provide this distinction.
Common misconceptions about body fat include believing that a low number on the scale automatically means low body fat (you could be losing muscle) or that body fat percentage is static and doesn't change with lifestyle. It's also often confused with BMI, which is a ratio of height to weight and doesn't distinguish between fat and muscle.
Our calculator provides an estimation of body fat by height and weight. For precise measurements, consult a healthcare professional using methods like DEXA scans, hydrostatic weighing, or skinfold calipers.
Body Fat Percentage Formula and Mathematical Explanation
Estimating body fat percentage from basic measurements like height and weight, age, and gender relies on statistical models rather than direct measurement. One commonly used approach involves first calculating Body Mass Index (BMI) and then using BMI along with age and gender in regression equations.
Step 1: Calculate BMI
The Body Mass Index (BMI) is a measure of body fat based on height and weight. The formula is:
$$ \text{BMI} = \frac{\text{Weight (kg)}}{\text{Height (m)}^2} $$
Where Height is converted from centimeters to meters (Height in meters = Height in cm / 100).
Step 2: Estimate Body Fat Percentage (BF%)
A widely cited regression equation developed by Deurenberg et al. (and adapted for common use) estimates BF% from BMI:
For adults:
$$ \text{BF\% (Male)} = (1.08 \times \text{BMI}) + (0.10 \times \text{Age}) – 19.4 $$
$$ \text{BF\% (Female)} = (1.08 \times \text{BMI}) + (0.10 \times \text{Age}) – 4.0 $$
*Note: Different formulas exist, and this is one common estimation. Some sources adjust slightly for age and gender.*
Step 3: Calculate Lean Body Mass and Fat Mass
Once BF% is estimated, lean body mass (LBM) and fat mass (FM) can be calculated:
$$ \text{Fat Mass (kg)} = \text{Weight (kg)} \times \frac{\text{BF\%}}{100} $$
$$ \text{Lean Mass (kg)} = \text{Weight (kg)} – \text{Fat Mass (kg)} $$
Variable Explanations:
Variables Used in Body Fat Estimation
Variable
Meaning
Unit
Typical Range
Height
The vertical measurement from the soles of the feet to the top of the head.
cm (converted to m for BMI)
140 – 200 cm
Weight
The total mass of the body.
kg
30 – 150 kg
Age
The number of years since birth.
Years
18 – 90 years
Gender
Biological sex, influencing body composition and fat distribution.
Male/Female
N/A
BMI
Body Mass Index, a ratio of weight to height squared.
kg/m²
15 – 40+
BF%
Body Fat Percentage, the estimated proportion of fat in the body.
%
5 – 50%+
Fat Mass
The absolute weight of fat in the body.
kg
Varies widely
Lean Mass
The absolute weight of non-fat components (muscle, bone, organs, water).
kg
Varies widely
Practical Examples (Real-World Use Cases)
Let's look at a couple of scenarios to understand how the calculate body fat by height and weight tool works.
Example 1: A Fitness Enthusiast
Scenario: Sarah, a 32-year-old woman, is training for a marathon. She's 168 cm tall and weighs 60 kg. She wants to understand her current body composition.
Interpretation: Sarah's BMI falls within the healthy range. Her estimated body fat percentage of 22.2% is within the "Fitness" category for women, which is excellent for an active individual. This indicates a good balance of muscle and fat, supporting her athletic pursuits.
Example 2: An Individual Concerned About Health
Scenario: David, a 55-year-old man, has a sedentary job. He is 180 cm tall and weighs 95 kg. He's concerned about his health and wants to know his body fat estimate.
Interpretation: David's BMI of 29.3 indicates he is overweight. His estimated body fat percentage of 17.8% falls into the "Fitness" to "Average" range for men. While this might seem moderate, his high BMI suggests that a significant portion of his weight could be excess fat mass contributing to health risks. The calculator helps him see that despite a seemingly "average" body fat percentage, his overall weight and BMI warrant attention and potentially lifestyle changes to reduce health risks.
How to Use This Body Fat Calculator
Our calculate body fat by height and weight tool is designed for ease of use and quick estimations. Follow these simple steps:
Enter Your Height: Input your height in centimeters (e.g., 175 for 175 cm).
Enter Your Weight: Input your weight in kilograms (e.g., 70 for 70 kg).
Enter Your Age: Provide your age in years (e.g., 30).
Select Your Gender: Choose 'Male' or 'Female' from the dropdown menu. This is crucial as body fat distribution and reference ranges differ between sexes.
Click 'Calculate Body Fat': Once all fields are filled, click the button.
How to Read the Results:
Estimated Body Fat (%): This is the primary output, showing your approximated body fat percentage.
BMI: Your Body Mass Index is displayed for context.
Lean Mass (kg): The weight of your non-fat body mass (muscles, bones, organs, etc.).
Fat Mass (kg): The weight of your body fat.
Decision-Making Guidance:
Compare your estimated body fat percentage to the Body Fat Percentage Reference Ranges table provided.
Healthy Range: Aim for a percentage within the "Fitness" or "Average" categories appropriate for your gender and age group.
High Body Fat: If your estimate falls into the "Obese" category, it's a strong indicator to consult with a healthcare provider about diet, exercise, and lifestyle modifications to reduce health risks.
Very Low Body Fat: Extremely low percentages (below "Essential Fat") can also be unhealthy and indicate potential issues like malnutrition or overtraining.
Remember, this is an estimation. For precise body composition analysis, consider professional assessments. Use these results as a motivational tool and a guide for setting health and fitness goals.
Key Factors That Affect Body Fat Results
While our calculator provides a useful estimation of body fat by height and weight, several real-world factors influence your actual body composition and can affect how these estimations align with reality.
Muscle Mass: This is the most significant factor not directly measured by this calculator. Individuals with higher muscle mass (athletes, bodybuilders) may have a higher BMI and potentially a higher estimated body fat percentage than they actually possess, as the formulas assume a typical body composition. Muscle is denser than fat, so high muscle mass can skew BMI-based estimations.
Bone Density: Similar to muscle mass, denser bones contribute to overall weight without being fat. While less impactful than muscle, it's another reason why BMI can be misleading for very muscular or heavily boned individuals.
Body Water Content: Hydration levels can fluctuate daily and affect total body weight. While not directly fat, significant water retention or dehydration can slightly alter weight and thus intermediate calculations like BMI and subsequent fat mass estimations.
Genetics and Fat Distribution: Where your body stores fat is largely determined by genetics. Some individuals tend to store more visceral fat (around organs), which is more detrimental to health but might not be perfectly captured by a general formula. The formulas used are averages.
Age and Hormonal Changes: As people age, metabolic rate often slows, and hormonal shifts (especially for women during menopause) can lead to changes in body composition, often favoring fat storage over muscle. Our calculator accounts for age to some extent, but individual hormonal profiles vary.
Dietary Habits and Metabolism: Chronic dietary patterns and individual metabolic efficiency play a huge role in how fat is gained or lost. While not directly input, these underlying factors influence the weight and body composition that the calculator uses. A calorie surplus leads to fat gain, while a deficit leads to fat loss.
Activity Level: Regular physical activity, especially resistance training, builds muscle and can decrease body fat. Conversely, a sedentary lifestyle promotes fat accumulation. The calculator doesn't directly measure activity level but uses age and gender as general proxies for typical body composition.
Frequently Asked Questions (FAQ)
What is the most accurate way to measure body fat?
The most accurate methods are generally considered to be Dual-energy X-ray absorptiometry (DEXA or DXA), hydrostatic weighing (underwater weighing), and air displacement plethysmography (Bod Pod). Skinfold calipers are also common but require a skilled technician for accuracy. Our calculator provides an estimate.
Why does my body fat percentage seem high for my weight?
This is often due to a higher muscle mass. Muscle is denser than fat. If you are physically active or have built significant muscle, your weight might be higher relative to your height (leading to a higher BMI), and the formula might overestimate body fat if it doesn't account for your muscularity.
Can body fat percentage change quickly?
While significant changes in body fat take time, short-term fluctuations can occur due to changes in water weight, diet (e.g., glycogen stores), and hydration. However, a true reduction or increase in fat mass is a gradual process influenced by consistent diet and exercise.
Is a lower body fat percentage always better?
Not necessarily. While reducing excess body fat is beneficial for health, very low body fat levels can be detrimental, impacting hormone production, immune function, and overall well-being. There is a healthy range for everyone, depending on age, gender, and activity level.
How does age affect body fat percentage estimations?
Age is factored into many body fat estimation formulas because metabolic rate tends to slow down, and body composition naturally shifts with age, often leading to an increase in body fat percentage if lifestyle habits don't adapt. Our calculator includes age to refine the estimate.
Can I use this calculator for children?
This calculator is designed for adults. Body composition calculations for children and adolescents are more complex and require age-specific formulas and considerations, often best done under the guidance of a pediatrician or registered dietitian.
What if my BMI is normal but my body fat percentage is high?
This condition is sometimes referred to as "normal weight obesity" or "skinny fat." It means that while your weight is within a healthy range for your height, a disproportionate amount of that weight is fat, and you may have lower muscle mass. This still carries health risks, and focusing on building muscle through resistance training and maintaining a healthy diet is recommended.
How often should I check my body fat percentage?
For general health tracking, checking every 1-3 months is usually sufficient. If you are in a specific training phase or undergoing significant lifestyle changes, you might monitor more frequently, but avoid daily checks as minor fluctuations can be misleading. Consistency in method (if using a tool other than this calculator) is also key.
Related Tools and Internal Resources
BMI CalculatorCalculate your Body Mass Index and understand its relation to your weight and height.