What This Calculator Does
The Gastric Sleeve Weight Loss Calculator estimates how much weight you may lose after a sleeve gastrectomy (gastric sleeve) procedure. It uses the widely-cited concept of Excess Weight Loss (%EWL), which measures how much of the weight above your ideal body weight you are expected to shed. Gastric sleeve patients commonly achieve around 60–70% EWL within the first 12–18 months.
How to Use It
Enter your current weight and your ideal weight (your goal or medically recommended body weight) in pounds. Then enter the expected %EWL — 60% is a conservative, realistic estimate for a gastric sleeve. The calculator returns your excess weight, the projected pounds lost, and your projected final weight.
The Formula Explained
First, excess weight is found by subtracting ideal weight from current weight. Then expected loss is that excess weight multiplied by the chosen percentage:
$$\text{Excess Weight} = \text{Current Weight} - \text{Ideal Weight}$$
$$\text{Expected Loss} = \text{Excess Weight} \times \frac{\text{\%EWL}}{100}$$
Projected weight is simply your current weight minus the expected loss:
$$\text{Projected Weight} = \text{Current} - E \cdot \frac{\text{\%EWL}}{100} \quad\text{where}\quad E = \text{Current} - \text{Ideal}$$
Worked Example
Suppose you weigh 250 lbs and your ideal weight is 150 lbs, with an expected 60% EWL. Excess weight = \(250 - 150 = 100\) lbs. Expected loss = \(100 \times 0.60 = 60\) lbs. Your projected weight = \(250 - 60 = 190\) lbs.
FAQ
Is this a medical guarantee? No. This is an educational estimate. Actual results vary widely based on diet, exercise, metabolism, and surgical factors. Always consult your bariatric team.
What %EWL should I use? Gastric sleeve outcomes typically range from 50% to 70% EWL. Use 60% for a balanced estimate or adjust based on your surgeon's guidance.
What if my current weight is below my ideal weight? Excess weight is treated as zero, so the calculator reports no expected loss.
