How Much Weightloss  Should I Expect Using Dr. Lipman’s Personalized GLP-1 Weight Loss  Calculator                       A modern digital interface showcases Dr. Lipman’s GLP-1 Expected Weight Loss Calculator. It features a clean layout with blue accents, crisp white backgrounds, and clearly labeled fields for current weight, age, sex, and medication selection to calculate ideal body weight.

 by Dr. Richard Lipman M.D. Internal Medicine/Endocrinology
Weight Loss Specialist
March 15th, 2026.


Your GLP-1 Weight Loss calculator from Dr. Lipman uses a small set of your personal factors—such as age, sex, starting weight, and  GLP-1 medication and specific dose—to estimate how much weight you might expect to lose taking  GLP-1 drugs at different dose levels.  One of the most common questions I hear from patients considering GLP-1 medications is “how much can I lose?”

GLP-1 Medications in Dr Lipman’s  Calculator:

Semaglutides (Qysmia and Wegovy) and and Tirzepatides   including Zepboound and Mounjaro are included.  Not enough data is available for the oral versions.

GLP-1 weight-loss medications, including Semaglutide and Tirzepatide, have transformed obesity treatment by addressing the biology of appetite, satiety, and recurrent intrusive thoughts about food,   termed food noises, rather than relying on willpower alone. Large clinical trials and real-world patient data consistently show predictable, dose-dependent weight loss when these medications are used correctly and combined with appropriate nutrition, exercise, and follow-up care. Use Dr Lipman’s algorithm to provide an estimate of the expected weight loss for various GLP-1 medications at different dose levels. Often you need to see what the ideal weight actually should be. See the ideal wt calculator. 

GLP-1-Weight Loss Algorithm  provides an estimated average weekly weight-loss range taking weekly injections of  Semaglutide or Tirzepatide, based on:

  • Your starting weight: It’s easier to have a large calorie deficit when you start losing weight at a higher weight. This, combined with losing more water weight at a higher starting weight, accounts for greater weight loss at the start of a weight-loss program, the higher the starting weight and the ideal weight the more the possibld weighy loss.

  • Sex and age: Gender and age play a minor role in the actual weekly weight loss. Some studies show women and
    Older people lose weight slightly more slowly than men and younger individuals.

  • The specific GLP-1 medication: There are significant differences in weight loss among the 4 major GLP-1 medications, with greater| weight loss with Mounjaro and Zepbound as compared to Ozempic and Wegovy. Compound preparations also offer significant weight loss.

  • The dose level of GLP-1 affects weight loss, with greater weight loss at higher doses.

  • Some of the results are based on Wishnofsky’s Rule from 1958. (see below). He bases the weight loss on the
    3500 calorie deficit= 1 lb weight deficit.

These estimates reflect what we typically see in patients who are properly titrated, medically supervised, and adherent to therapy. Individual results may vary, but this tool gives you a realistic starting point for setting expectations and planning your journey.

Use the Calculator below to see your Personalized Weight Loss Estimate on GLP-1 Injections  

Click Me  CLICK THE RED LINK:   lipman-calclipman-calculator-htmlOPENWIHITEREADY T GIweight

How this information can make your weight loss successful

Dr. Lipman’s weight loss calculator helps patients recognize the expected weight loss across thousands of patient visits and then set realistic goals based not on informational inserts in the medication box, but on patients who match the user’s age, sex, medications, and metabolic status. This prevents early discouragement and unrealistic.
Weight loss does not happen at the same rate for everyone, and results depend on factors such as dose, appetite, diet, activity level, diabetes, concurrent medical problems and medications as well as starting weight. Drug tolerability also plays a huge role in the rate of weight loss.

Knowing What to Expect Makes Weightloss Easier

A guide to expected weight loss can show who is responding as expected, who might need more time or a dose change, and who may need a different plan. It is important to have realistic expectations because GLP-1 medications work well, but they are not a quick fix. The aim is steady, safe weight loss under medical supervision, not fast or risky results. Knowing what to expect helps patients stay motivated, notice progress, and avoid quitting treatment too soon due to unrealistic expectations or taking doses that are both high and low for months at a time.

 

Development of Wishnofsky’s Rule
Max Wishnofsky asked in a 1958 report “What is the caloric equivalent of one pound of body weight gained or lost?”1 After a thoughtful analysis of the existing literature, Wishnofsky concluded that “the caloric equivalent of one pound of body weight lost” or “gained will be 3500”. Fifty years later and with thousands of citations in the scientific literature and the lay press, Hill and his colleagues repeated the oft-used statement “an energy deficit of approximately 3500 kcal is needed to lose 1 lb of body weight” i