Omni Calculator logo

Gastric Sleeve Weight Loss Calculator

Created by Michael Darcy and Aleksandra Zając, MD
Reviewed by Dominik Czernia, PhD and Jack Bowater
Based on research by
Weight Loss Estimator; Bariatric Surgery Source; 2021
Last updated: Jan 18, 2024

If the thought of undergoing bariatric surgery has crossed your mind recently, our gastric sleeve weight loss calculator may help you make an informed choice. Wondering "Do I qualify for the gastric sleeve?"? Well, we can try to answer that.

You'll also find an answer to "What is a gastric sleeve?", as well as weight loss projection based on your initial body mass, all presented on a gastric sleeve weight loss chart. You'll also be able to compare different types of weight loss surgery. Sounds interesting? Then read on!

We try our best to make our Omni Calculators as precise and reliable as possible. However, this tool can never replace a professional doctor's assessment. If any health condition bothers you, consult a physician.

Who is a "bariatric patient"?

The word bariatric refers to things related to the treatment of obesity. It follows that a bariatric patient is an obese person whose body mass index (BMI) exceeds 30. However, in practice, it's mostly used to refer to morbidly obese individuals with a BMI over 40.

Why is there a specific name for these patients? Well, it's primarily meant to address the fact that obese patients may have slightly different needs that the hospital needs to account for. For example, tissue viability or manual handling can be more challenging in bariatric patients. Ensuring that the clinic is adequately equipped (e.g., has bariatric beds available) and staffed is crucial to providing proper care.

Since obesity yields an increased risk of some health conditions, patients may be additionally monitored by doctors - which is great, considering that an early diagnosis can save a life. The only thing better than prompt detection is prevention, which brings us to the following question: Do I qualify for a gastric sleeve (or other bariatric surgery)?

Do I qualify for the gastric sleeve? BMI for weight loss surgery

Not everyone can undergo bariatric surgery, especially if they don't wish to pay for it out of their own pockets. What if you decided this option was for you after seeing bariatric weight loss charts or someone's gastric sleeve results? How do you know you're eligible? Well, although each case is unique, there are a few indicators that you may qualify for a gastric sleeve:

  • You need to have the right BMI for weight loss surgery - you can check yours with the BMI calculator. This is usually above 40, or 35 if you have an obesity-related condition that might improve with weight loss, such as:

    • Type 2 diabetes;
    • High blood pressure;
    • Sleep apnea;
    • High cholesterol; and
    • Joint issues.
  • You're healthy enough for surgery under general anesthetic.

  • Often, you need to show a history of unsuccessful dieting and exercise or that you had difficulty keeping the weight down.

  • You must be psychologically ready to commit to the lifestyle changes after the surgery. The procedure is meant to help you lose weight, but nevertheless, you will need to follow a balanced diet, exercise, and attend follow-up appointments. Calories burned calculator can give you an idea of what activities are the most weight loss friendly.

Bear in mind that these are just general guidelines. Remember to consult your doctor for personalized advice. And if you've already concluded that a bariatric procedure is suitable for you, it's time to consider which surgery is better for weight loss. The good news is, the mathematics behind the gastric sleeve weight loss calculator may have the answer.

Which surgery is better for weight loss?

Even if you don't watch the news, you're probably aware that obesity has become a major issue and it doesn't seem like it's going to change anytime soon. We've come up with many ways of dealing with this problem, including different types of weight loss surgery. This means that if you're eligible for all of them, you have many options to choose from. Which surgery is better for weight loss? Let's compare the options:

  • AspireAssist is a relatively new method. Its main pros are that it's reversible and not as invasive. It uses a small tube and a device that allows you to remove approximately 1/3 of food from your belly. However, you should expect to lose only about 30% of your excess weight.
  • Gastric balloon is inserted inside your stomach and makes you feel fuller, resulting in smaller food portions. It's inserted orally, so it doesn't require any vital surgery. You can lose up to 30% of excess weight within six months; however, the balloon cannot remain in place any longer.
  • Lap-Band uses a gastric band that's placed around your stomach to limit the amount of food you can eat. It's adjustable and removable, making it one of the safest options. The weight loss projection is about 40% of your excess weight.
  • Duodenal switch weight loss timeline is where we see more impressive progress as you can shred up to 65% of the extra pounds (or kilograms). However, it comes at a price. The process is invasive, and there's a risk of malnutrition as only approximately 1/6 of your small intestine is left to absorb nutrients.
  • Gastric bypass (or Roux-en-Y) divides your stomach into two pouches - meals go to the smaller part and then directly to your bowels, so you feel fuller sooner. The results and progress are very similar to those of the duodenal switch weight loss timeline.
  • Gastric sleeve results are also excellent. So, how much weight can you lose with the gastric sleeve? It allows patients to lose as much as 70% of their extra weight. Again, there's something to sacrifice here - although the nutrient absorption is typically better, the part of your stomach that was removed won't come back.

The gastric sleeve weight loss calculator focuses on the last option as it's the most popular choice in many countries. However, you may not need such an invasive procedure to lose weight - that's why speaking to a professional is essential to see which one of the different types of weight loss surgery would be the most beneficial for you. The average monthly weight loss after gastric sleeve may look appealing, but comes with consequences you need to be aware of.

How to use the gastric sleeve weight loss calculator? Bariatric weight loss chart

Simply knowing the percentage loss for every surgery may not tell you much. How much exactly will you lose? How close to your ideal weight can you get? It's easy to find out with the gastric sleeve weight loss calculator.

Let's assume that you're 5 feet 6 inches tall (170 cm) and weigh 289 pounds (~131.1 kg). This means that your BMI is 45.4, and it's likely that you'd qualify for most of the different types of weight-loss surgeries. Inputting these values into the BMI calculator for gastric sleeve shows you your weight loss projection over 3, 6, and 12 months. We can represent our findings using the bariatric weight loss chart:

Bar chart showing weight loss projection for different surgery types.

Bear in mind that these values aren't fixed and will most likely vary slightly. A good way of maximizing your results is by incorporating various forms of activity, such as walking or cycling.


How to calculate weight loss after gastric sleeve?

Although your final weight will depend on many factors, such as your diet and activity level, you can follow these steps to estimate your gastric sleeve results:

  1. Find your ideal weight, for example, by using a BMI calculator. In this case, we use the upper limit - 24.9.
  2. Subtract the ideal weight from your current weight to find your excess weight.
  3. Multiply the excess weight by 0.6 to see how much weight you will most likely lose with a gastric sleeve.

How much do you have to weigh for gastric bypass?

Since the ideal weight depends mainly on your height, doctors use BMI to assess their patients rather than just their body mass. In most cases, to qualify for gastric bypass, your body mass index should exceed 40. This number can be lowered to 35 if you have any obesity-related conditions.

What is the safest form of weight loss surgery?

Out of many available bariatric surgery methods available, gastric band is considered the safest. It is rather simple, and the good news is that the band can be removed, contrary to a gastric sleeve which is irreversible.

How to convert my weight from 109.6 kg to lbs?

To convert your weight from kilograms to pounds, multiply it by 2.205. In this case, we have 109.6 × 2.205 = 241.6 lbs. If you wanted to calculate it the other way round, you need to divide the number of pounds by the same number (2.205) to obtain kilograms.

Michael Darcy and Aleksandra Zając, MD
Related calculators
Surgery type
Gastric sleeve
Check out 30 similar dietary calculators 🥗
Added sugar intakeBasal energy expenditureBMR - Harris-Benedict equation… 27 more
People also viewed…

Blood donor

This blood donor calculator checks the compatibility for donating and receiving blood or blood plasma.

Glycemic load

The glycemic load calculator estimates the glycemic load of a food product, which tells you how eating it will affect your blood sugar levels.

Ideal egg boiling

Quantum physicist's take on boiling the perfect egg. Includes times for quarter and half-boiled eggs.


The sleep calculator can help you determine when you should go to bed to wake up happy and refreshed.
Copyright by Omni Calculator sp. z o.o.
Privacy, Cookies & Terms of Service