Our weight loss calculator is a tool to help you find out exactly what you need to do to get to your desired weight.

Weight Loss Calculator

Calculate what you need to do to achieve your weight loss goals.

Activity Level:

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Our Weight Loss Calculation

Our calculator uses the information you provide (age, height, current weight, desired weight, goal date) to calculate a specific value of calories you must consume (i.e. how much you should eat) every day in order to meet your weight loss goal. Essentially, it is a way to see, in an instant, your potential weight loss based on your current health and goals.

Because this calculation is based entirely on the data you provide, it's very important to be as accurate as you can, particularly when selecting your activity level. You should select the activity you expect to maintain over the course of your weight loss plan — not what you hope to be able to do, but what you will actually be able to do.

Example Calculation

For example, to show the importance of accuracy, take a hypothetical woman named Sarah, who is determined to lose weight (say 10 pounds) in two months. Let's say these are her stats:

  • Age: 35
  • Height: 65 inches (5'5")
  • Current weight: 150
  • Desired weight: 140
  • Activity level: 4 (frequent activity)
  • Date to lose by: 2 months from now

Based on this information, her body consumes 2374 calories per day and she'll need to have a caloric restriction of 593 in order to lose 10 pounds in 2 months — which means she'll need to consume around 1781 calories every day.

Notice that she selected an activity level of 4, which stands for frequent activity, or exercising pretty much every day. She selected this level because it was what she hoped to be able to achieve. However, if she is unable to work out with this frequency over the two month period, her daily energy consumption will drop as well, meaning she'll need to consume fewer calories than the initial calculation.

Under some circumstances — say if she misses a day or two every other week — the difference may be only slight. But it's certainly worth taking note of because if she doesn't realize it and continues consuming the same amount of calories based on the previous calculation, she may end up gaining weight!

Important takeaway: Accuracy is key. This means knowing yourself and figuring out, based on your schedule and motivation levels, how frequently you'll actually be able to work out.

Now let's delve into further details of how we arrive at our calculation for losing weight.

Calculating Weight Loss: How Does it Work?

Our weight loss calculator uses the data you enter to determine the daily caloric deficit you must maintain to lose the weight you want to lose by the date you want to lose it. In addition to this, we provide a list of recommended dietary supplements that may enhance your efforts of losing weight.

Weight Loss Calculator Results Woman

To get the final calculation, our weight loss calculator first calculates your BMI, BMR, and TDEE, all of which are explained in more detail below.


While this may seem like just a simple mathematical calculation, there is a little more to it than that. To get to an accurate calculation, we first find your body mass index (BMI), which is a gauge of your body fat based on your height, weight, and gender. (We also have a BMI Calculator). However, the BMI calculation is vulnerable to many limitations, so using it as a standalone measurement may not tell you much. For example, a person with a lot of muscle may in reality be extremely healthy and have low body fat, but his/her BMI result will indicate that he or she is overweight. For this reason, in our calculations we use several other measurements in addition to BMI.


We then use your BMI calculation to determine your basal metabolic rate (BMR), which is the daily amount of calories you consume at rest — meaning the calories you naturally burn every day without doing anything. Yes, it's true! Your body burns calories when you do nothing, and a ton of them by the way. (You can also try out our BMR Calculator). Like with BMI, however, certain limitations also apply to the BMR calculation. For example, muscle burns more calories than fat — thus, if two people weigh the same but one has more muscle and the other has more fat, the person with more muscle is going to have a higher BMR. Because of this, we take our calculations even further than BMR.


We use these measurements (BMI and BMR) to calculate your total daily energy expenditure (TDEE), which is just what it sounds like — the total amount of energy you spend every day. (Check out our TDEE Calculator.) While similar to your basal metabolic rate, the measurement of your total daily energy expenditure also considers your activity level throughout the day, and is therefore a more accurate reading of how many calories you burn per day (as even the most talented couch potatoes expend more energy than their BMR indicates — don't knock the exercise potential of lifting a remote!).

Finally, making use of all of these calculations, we arrive at the amount of calories you need to restrict per day in order to lose the amount of weight you want by the date you want to lose it by.

Is this guaranteed to work?

While the body and losing weight is very scientific and can be examined on a mathematical level, losing weight is as much an art as it is a science. The simple truth is that everyone's body is different and will respond differently to various stimuli.

If your goal is to lose weight, the key is to find what works best for you, and the only way to do this is by trial and error. But know that by being here, researching and learning, you are certainly on the right path to succeeding in your weight loss goals.

More Information

To aid you on your journey to weight loss, we recommend subscribing to our blog, if you haven't already. We are continually publishing articles with tips for getting and staying healthy, and by subscribing you will get notification of new articles as they are posted. This additional information can only help you to lose weight. If you'd like, you can head over to our blog right now and start reading what we've already published.