GLP-1 Weight Loss Calculator

This calculator uses average weight loss data from published clinical trials (STEP 1, SURMOUNT-1, OASIS 1). Individual results vary significantly based on diet, exercise, starting weight, dosage, and how your body responds to the medication. These projections are estimates, not guarantees.

Most people see the fastest weight loss in the first 6 months as the dose is gradually increased. Weight loss typically slows around months 8-12 as the body reaches a new equilibrium. On average, people lose 12-21% of their body weight over about 15-17 months depending on the medication.

In clinical trials, tirzepatide (Zepbound/Mounjaro) showed average weight loss between 16% and 22.5% depending on dose (16.0% at 5 mg, 21.4% at 10 mg, and 22.5% at 15 mg in SURMOUNT-1), with most published results citing approximately 21% for the commonly prescribed 10 mg dose. Semaglutide (Wegovy) averaged about 15%. However, the best medication for you depends on your health history, insurance coverage, budget, and how you respond to treatment.

Retail prices for brand-name injectable GLP-1s without insurance are commonly reported in the $1,300-$1,800 per month range as of June 2026, though this varies by dose and pharmacy. Manufacturer direct-pay programs can reduce this significantly: oral semaglutide (the Wegovy pill) is available for as low as $149-$299/month through the manufacturer's program, and injectable options range from roughly $199-$499/month depending on dose and program terms. Compounded versions typically cost $200-$250/month but are not FDA-approved and should not be considered equivalent to brand-name products; formulation, concentration, and quality control can vary between compounding pharmacies. Prices change frequently; visit our Cost Guide for current details.

Yes, all GLP-1 medications require a prescription from a licensed healthcare provider. You can get prescribed through an in-person clinic or a telehealth provider. Use our directory to find providers near you or compare online options.