Enter your initial weight and final weight (or goal weight) into the calculator to determine the percentage of weight you have lost.

Weight Loss Percentage Formula

The following formula can be used to calculate weight loss as a percentage.

WL% = (OW – FW) / OW *100

  • WL% is the percentage of body weight lost
  • \Where OW is the original body weight
  • FW is the final body weight

Weight Loss Percentage Definition

A weight-loss percentage is a ratio, known as a percentage, of your initial body weight over your final body weight, or goal body weight. The reason looking at weight loss in a percent is useful is because, for extremely light people, it may be very difficult to lose 5lbs, but as a percentage of total body weight, it would equal a much large amount if they weighed a lot more.

This puts into perspective the perceived difficulty of losing weight. Let’s say there’s a 500lb man and he loses 50 lbs. You might and should think that is a huge accomplishment because it is. But how does that compare with the weight loss of someone weighing 200lbs? While not a direct correlation because weight loss depends on many factors, you could visualize that weight loss as the same as 20lbs on the 200lb man.

How to calculate weight loss as a percent

The following example is a step-by-step guide on how to calculate weight loss as a percent of total body weight. For this example, we will assume that someone is trying to lose weight, and has a goal final weight in mind.

  1. The first step is to measure your current weight. This should be done 3 times throughout the day, and the result should be averaged. This is to account for fluctuations in weight that occur throughout the day. Let’s say you weigh in at 178, 179, and 177. The average would be 177lbs.
  2. The next step is to determine your goal weight. Let’s assume you have a weight lifting competition you are training for and you need to make a weight class of 155 lbs. That would be a weight loss of 22 lbs, but what is that in a percent?
  3. The final step is to use the formula or calculator above to determine the percentage. OW-FW/OW*100 = 177-155/177*100 = 12.43%.
  4. Analyze the results and put a diet plan into action in order the meet your goal. Note that a healthy weight loss rate is no more than 2 lbs per week.

FAQ

What is a weight loss percentage?

A weight-loss percentage is a ratio, known as a percentage, of your initial body weight over your final body weight, or goal body weight.

weight loss percentage calculator
weight loss percentage formula

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