# GLP-1 Weight Loss Curve Calculator

> Free calculator that plots expected percent weight loss over 72 weeks for semaglutide 2.4 mg (Wegovy), tirzepatide 5/10/15 mg (Zepbound), oral semaglutide 25 mg and liraglutide 3.0 mg, using published phase 3 trial means, and computes a daily protein target (1.2–1.6 g/kg).

Key facts (trial means, percent of starting body weight):
- Semaglutide 2.4 mg, STEP 1: −6.0% at week 12, −14.3% at week 52, −14.9% at week 68. Placebo −2.4%.
- Tirzepatide 15 mg, SURMOUNT-1: −7.5% at week 12, −19.5% at week 52, −20.9% at week 72. 10 mg −19.5%, 5 mg −15.0%.
- Oral semaglutide 25 mg, OASIS 4: −13.6% at week 64.
- Liraglutide 3.0 mg, SCALE: −8.0% at week 56.
- Head to head SURMOUNT-5: tirzepatide −20.2% vs semaglutide −13.7% at week 72.
- Curves plateau between weeks 40 and 60 for all agents.
- Regain: STEP 1 extension — two-thirds of lost weight regained one year after stopping semaglutide. SURMOUNT-4 — switching tirzepatide to placebo regained +14% over 52 weeks vs −5.5% further loss on continued drug.
- GI side effects (drug vs placebo): semaglutide 2.4 mg nausea 44% vs 17%; tirzepatide 15 mg nausea 31% vs 10%; liraglutide 3.0 mg nausea 40% vs 15%.
- Head-to-head STEP 8: semaglutide −15.8% vs liraglutide −6.4% at 68 weeks.

Pages:
- [Track your curve](https://weighweekly.com/track.html): Save a projection, log your weight each week, and see your real curve drawn against the published trial mean. Runs in the browser, no account.
- [Cost and cost per pound](https://weighweekly.com/cost.html): Self-pay, insured and list prices for Wegovy, Zepbound, Ozempic, Saxenda and oral semaglutide, divided by expected trial weight loss to give a cost per pound.
- [If you stop](https://weighweekly.com/rebound.html): Projected weight regain after stopping, from the withdrawal arms of STEP 1 extension, STEP 4 and SURMOUNT-4, against the continued-treatment arm.
- [Compare drugs](https://weighweekly.com/compare.html): overlay chart of all six trial curves plus a table of mechanism, titration, approved uses, side-effect rates, cost and who each suits.
- [Side effects by week](https://weighweekly.com/side-effects.html): trial rates, what to expect after each dose step, fixes, red-flag symptoms, contraindications.
- [Calorie calculator](https://weighweekly.com/calories.html): Mifflin-St Jeor TDEE, deficit options, intake floor, protein target for GLP-1 users.
- [Keeping it off](https://weighweekly.com/maintenance.html): STEP 1 extension and SURMOUNT-4 regain data, maintenance calorie calculator with adaptive thermogenesis, five maintenance habits.
- [Habit tracker](https://weighweekly.com/habits.html): seven evidence-based daily habits, saved locally.
- [Where to get it](https://weighweekly.com/providers.html): Ro, Hims, Found, LillyDirect/NovoCare, own doctor compared; why to avoid compounded products.
- [Calculator](https://weighweekly.com/): enter weight, height, medication; optional current weight + weeks to plot your position vs the trial curve.
- [Methods and sources](https://weighweekly.com/methods.html)
- [Dataset, JSON, CC BY 4.0](https://weighweekly.com/trials.json)

Not medical advice. Data may be reused with attribution to weighweekly.com.