Weight Loss Calculators

There are many ways to determine your ideal body weight and composition. At RE•BODY®, we like to use these calculators to track and measure your ideal body composition and weight. We have included the best weight loss calculators below to help you determine what your goals are.

Estimated Body Fat %
U.S Navy Circumference Method Learn More


Your Height:



My Result

Estimated % Body Fat:


Ideal Weight
Based on American Council of Exercise Learn More

Your Current Weight:

Current Body Fat%:

You can estimate this using the body fat calculator, at left. Or Click Here for more accurate measurement methods.

Your Ideal Body Fat % Goal:

  1. 1

    Click Here to choose your ideal body fat % goal. Enter your goal below.

  2. 2
My Result

Based on your target of 19.6% body fat, your ideal target weight is:


Waist Circumference
Measure your natural waistline Learn More

Waist Measurement:

Your Height:

My Result

You are above your maximum ideal waist circumference of.


Waist to Hip Ratio
Measure your natural waistline Learn More


Waist Measurement:

Hip Measurement:

My Result

Ideal range: 0.70 - 0.75

extremly high

Body Fat Percentage Alternate Methods

Fold Caliper (Pinch Test).
The Accu-Measure Fitness 3000 Personal Body Fat Tester

Home Scale With Body Fat Measurement.
Bioelectric Impedance Analysis (BIA)

DEXA Scan. This X-ray technology measures bone mineral density.
You may want to explore whether you are eating the right foods to strong healthy bones.

Hydrostatic Weighing. As you might expect from the word hydro, this technique multiplies the density of the body and the density of water to analize body composition and measure the mass per unit volume of a patient's body. It's also known as underwater weighing.

Body Fat Percentage, The U.S. Navy Circumference Method *

Your current body fat percentage: There are many ways to determine your body fat percentage. We have included a calculator to give you an estimated percentage.

To determine your Estimated Body Fat Percentage, you will need the following measurements:

Height (Both) - without shoes.
Neck (Both) - inferior to the larynx with the tape sloping slighly downward to the front.
Waist (Women only) - Horizontal, at the level of minimal abdominal width.
Abdomen (Men only) - Horizontal, at the level of the navel.

From the numbers above, we can tell you what your estimated body fat should be. Enter your measurements into the appropriate calculator.

* From Hodgdon, J. and Beckett M. Prediction of percent body fat for U.S. navy men and women from body circumferences and height. Reports No. 84-29 and 84-11. Naval Health Research Center, San Diego, California 1984

What is My Ideal Body Fat Percentage?

Now that you know what your current body fat percentage is, use the chart below to chose your Target Body Fat Percentage goal. For example, if Karen's current body fat percentage is 30%, she may have a goal to be at 25%. She would enter 25% in the calculator.

Choose your Target Body Fat Percentage goal and enter in calculator.




Essential Fat













32% and higher

25% and higher

From The American Council of Exercise.

The formulations below are based on The American Council of Exercise's recommendations. Our calculators do all of the math for you. If you love math and want to calculate your Ideal Body Weight yourself, here are the formulas.

Ideal Body Weight Calculation = Lean body weight/(1-desired body fat percentage).

Ideal Body Weight = Your weight when you are at your desired body fat percentage.

Lean Body Weight = All the mass in your body that is not fat.

Desired Body Fat Percentage = Your goal body fat percentage (in decimal form).
For example, Sara weighs 150lbs and has 29% body fat (43.5lbs fat, 106.5lbs lean). Her goal is to have 24% body fat. How much weight will she need to lose (assuming all of the weight loss comes from fat)? Desired body weight = 106.5/(1-.24) = 140lbs. So she would need to lose 10lbs to achieve her goal (150-140=10lbs).

Waist Circumference Measurement

Measure your waist once a month. Be sure to measure at your natural waistline-the area above your hip bone and below your rib cage. Think of it as the area where your hand would land if you put your hand on your hip. It's lower than where you wear your belt and closer to your belly button.

Be sure to suck in your belly so you can measure the omentum fat that lies deep within the belly.

A waist size of more than 35 inches in a woman and more than 40 inches in a man indicates that you and your good health will reap more benefit from loosing weight.

Your ideal waist size is half your height in inches. For example, if you are 5'5" tall, your height in inches (65)--divided by 2--is 32.5". You don't want your waist size to exceed your ideal waist size for your height.

Waist to Hip Ratio

The Waist-to-Hip Ratio is used to measure your health and your risk of develping a serious health condition. Research has shown that people who carry more weight around their waistlines face greater health risk than people who carry more weight around their hips.

The World Health Organization defines "obese" as a man with a Waist-to-Hip Ratio above 0.90 and a woman with a ratio above 0.85.

  For Women:

  • < 0.75
  • 0.75-0.79
  • 0.80-0.84
  • 0.85-0.90
  • > 0.90
  • Excellent
  • Fair
  • Average
  • High
  • Extreme

  For Men:

  • < 0.85
  • 0.85-0.89
  • 0.90-0.94
  • 0.95-1.00
  • > 1.00
  • Excellent
  • Fair
  • Average
  • High
  • Extreme
Meratrim available at these fine retailers
International Retailers

Δ SAFActive78™, patent-pending No. 61/430,596

Please check with your healthcare professional before taking this product if you are pregnant, nursing, under a doctor’s care or taking medication.

† All RE·BODY products are intended to be used in conjunction with a reduced calorie and exercise program.

* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.