Body Fat Percentage Calculator

Use this calculator to estimate your body fat percentage.

This is a good tool for measuring fat loss progress since the scale isn’t always accurate due to weight fluctuations.

What is Body Fat Percentage?

Body fat percentage is the proportion of your bodyweight that is comprised of fat tissue.

Body fat percentage usually relates to your fitness level and it can be a better indicator of health than your BMI.

Here’s how the American Council on Exercise relates the body fat percentage of men and women to their level of fitness.

*Men are considered borderline at 25% body fat and clinically obese at 30%, while women are borderline at 30% and clinically obese at 35% body fat.

**A lower body fat percentage for women increases chance of amenorrhoea (cessation of menstruation).

How Tracking Body Fat Percentage is Useful When Counting Macros

Measuring and tracking body fat percentage is normal when counting macros for several reasons.

1. Knowing your body fat percentage is important in formulating an accurate TDEE (total daily energy expenditure). Most standard formulas base their calculations on what is considered to be an “average” body fat percentage. Therefore, those with a high BF% or those with a low BF% will have skewed results when using the standard TDEE formula. Special calculations are needed for obese individuals as well as those that are very fit.
2. Most flexible dieters are aiming to decrease their fat mass and increase their muscle mass. Tracking BF% change is a great way of tracking progress.
3. Knowing your body fat percentage allows you to calculate how many pounds of fat your body has. This helps you establish a realistic and healthy goal weight.

What About Electronic Devices?

Electronic body fat percentage devices have become pretty popular but I’ve found most to be inconsistent and inaccurate. In fact, don’t even bother using the scales with BF% built-in or those handheld devices.

Some gyms have immersion tanks and these are probably the most accurate for measuring BF% electronically. Apart from that, using calipers with the skinfold method is the best option and will provide you with a better estimation.

Having Body Fat is Healthy

Having some body fat is healthy and the body actually needs fat tissue to regulate hormone production and body temperature. Having too low BF% poses health risks.

Alarmingly, there’s a trend with men in the IIFYM community to get down to an extremely low BF% where the skin is so void of fat that just about every muscle striation is visible.

This isn’t sustainable or healthy. Guys really shouldn’t strive for anything lower than 5% and women 13% if they want their bodies to function optimally.

How to Calculate Lean Body Mass

If you know your body fat percentage then you can quickly calculate your lean body mass. Simply convert your body fat percentage to pounds of fat and then subtract this from your total body weight. This will be your lean mass.

Example: If you are a woman who weighs 160 pounds and has a body fat percentage of 26% then you have 41.6 pounds of fat (160x.26) and 118.4 pounds of lean mass (160-41.6).

How to Calculate Muscle Mass

If you have calculated your body fat percentage, then you are just a few steps away from calculating your muscle mass. Your muscle mass will make up the bulk of the weight of your lean mass which is your body fat weight subtracted from your total weight.

Your bones make up 12-15% of your body weight. 12% for woman and 15% for men. (This is an average but it gives you a good estimate.)

Other bodily tissues like nervous, skin, connective, and lymphatic make up about 25%.

Therefore, your muscle mass will make up the remainder of your body weight. This is generally 40-50% but depends on your body fat percentage and what’s left over after subtracting the other weight from your other tissues.

Example: If you are a man and weigh 190 pounds with 15% body fat, here’s how to calculate this man’s muscle mass:

• 190x.15= 28.5 pounds of fat.
• 190x.15= 28.5 pounds of bone.
• 190x.25= 48 pounds of other tissues.
• 190x.45= 85.5 pounds of muscle.

How to calculate your muscle mass in kg

If you want to convert your muscle mass from pounds to kilograms you can do so with some simple math.

1 lb = 0.45359237 kg

So if you have 85.5 pounds of muscle like the guy in the above example you would have 38.8 kg of muscle.

85.5 x 0.45359237 = 38.78

Other Helpful Calculators

See also the IIFYM Macro Calculator and Ideal Body Weight Calculator.

Ted Kallmyer is an ISSA certified Specialist in Fitness Nutrition, a Certified Fitness Trainer, and is Healthy Eater's author and nutitional coach. If you need help reaching your weight loss/fitness goals see his personal macros coaching options.