Free tools
38 GLP-1 calculators & simulators
Every calculation is cited to FDA labeling or published trial data, and the sources are listed on each tool’s own page.
Dosing & titration
Convert a prescribed dose to syringe units, plan a titration ladder, reconstitute a lyophilized vial, or read a pen.
Brand-Switch Dose-Equivalence Calculator
Switching from Wegovy to Zepbound, Foundayo to Saxenda, or any other FDA-approved weight-loss GLP-1? This tool surfaces the FDA-label §2 dose ladders, re-titration rules, and cross-trial efficacy caveats for all four drugs (Wegovy, Zepbound, Foundayo, Saxenda) so you walk into your prescriber appointment informed.
Open tool →GLP-1 Dose Plotter
Interactive PK simulator for GLP-1 receptor agonists. Plots plasma concentration build-up across 4 drugs (semaglutide, tirzepatide, orforglipron, retatrutide) using FDA-label half-lives and published PK literature.
Open tool →GLP-1 Missed Dose Guide
What to do if you miss a dose of Wegovy, Ozempic, Zepbound, Mounjaro, or Foundayo. Drug-specific guidance sourced directly from each FDA prescribing information label.
Open tool →GLP-1 Pen Leftover Calculator
Free calculator for how many doses are left in your Ozempic or Saxenda multi-dose pen, built on FDA-label fill volumes and dose counts.
Open tool →GLP-1 Reconstitution Calculator
BAC water + concentration + U-100 unit math for compounded GLP-1 vials. Hard FDA-max-dose guards and ISMP-aligned safety warnings.
Open tool →GLP-1 Reverse Dose Calculator (Units → mg)
Enter your syringe units and vial concentration to find the exact milligrams you're injecting. For compounded semaglutide and tirzepatide. Uses the U-100 insulin syringe standard.
Open tool →GLP-1 Split Dose Calculator
Calculate how to split a weekly GLP-1 dose into 2 or 3 smaller injections. For patients who experience side effects at full weekly dose. Includes syringe unit math at any vial concentration.
Open tool →GLP-1 Titration Schedule Planner
Build a personalized week-by-week titration schedule for Wegovy, Ozempic, Zepbound, Mounjaro, or Foundayo. Start date, dose escalation dates, and reminders — all from FDA-label titration protocols.
Open tool →GLP-1 Unit Converter
mg ↔ insulin syringe units for compounded GLP-1 vials. Pure-math, FDA-label-anchored.
Open tool →GLP-1 Vial Label Reader
Tap any field on a compounded semaglutide/tirzepatide vial label to decode it — concentration, BAC water, units vs mg, BUD — plus a calculator that turns your label into the exact units to draw.
Open tool →GLP-1 Vial Transition Calculator
Switching vial concentrations? Calculate your new syringe units when your compounding pharmacy changes your semaglutide or tirzepatide concentration. Prevents the #1 compounded GLP-1 dosing error.
Open tool →Mounjaro KwikPen Click & Dose Chart
Complete Mounjaro (tirzepatide) KwikPen reference: all 6 dose strengths, pen colors, titration schedule, storage, and administration steps. Sourced from the Mounjaro FDA prescribing information.
Open tool →Peptide Reconstitution Calculator
Free peptide reconstitution calculator. Enter your vial size in mg, the bacteriostatic water you added in mL, and your prescribed dose in mcg — get the exact draw volume, U-100 syringe units, and doses per vial. Converts a dose your prescriber gave you; it does not recommend one.
Open tool →Zepbound Pen Dose & Administration Chart
Complete Zepbound (tirzepatide) auto-injector reference: all 4 dose strengths, pen colors, titration schedule, storage, and injection steps. Sourced from the Zepbound FDA prescribing information.
Open tool →Cost & insurance
What you will actually pay, whether your plan covers it, and what to send the payer when it does not.
GLP-1 Cost Per Pound Lost Calculator
Free calculator that converts GLP-1 monthly price into dollars per pound lost using STEP-1, SURMOUNT-1, ATTAIN-1, and SCALE trial data.
Open tool →GLP-1 Prior Authorization Letter Generator
Free GLP-1 PA letter generator. Build a Wegovy, Zepbound, Saxenda, or Foundayo prior authorization letter using FDA-label language and pivotal trial citations.
Open tool →GLP-1 Savings Calculator
Calculate how much you'd save by switching between brand-name Wegovy, Zepbound, compounded semaglutide or tirzepatide, and Foundayo.
Open tool →Insurance Employer Checker
Look up GLP-1 weight loss drug coverage by employer, with verification metadata per entry.
Open tool →Skin-Removal Cost & Insurance Qualifier
Free panniculectomy / brachioplasty / thighplasty insurance pre-screen. Enter your peak BMI, current weight, months at stable weight, and insurer; the tool returns the CPT 15830 / 15847 / 15877 medical-necessity-criteria match against Aetna CPB 0211, Cigna 0192, UnitedHealthcare medical-policy 2023T0570U, and Anthem CG-SURG-58 — plus an ASPS-anchored cash-pay range when coverage is unlikely.
Open tool →State Medicaid GLP-1 Eligibility Pre-Screener
Look up your state Medicaid program's verified coverage of GLP-1 receptor agonists across six indications: chronic weight management, cardiovascular risk reduction, obstructive sleep apnea, MASH/NASH, pediatric (ages 12+), and type 2 diabetes. Every state surface includes a verbatim primary-source quote, verified-date badge, PA mechanics, appeal pathway, PBM identity, and a link to the full state research article.
Open tool →Safety & side effects
Interactions, side-effect timing, washout windows, surgery holds, injection-site rotation, and pharmacy legitimacy.
GLP-1 Drug Interaction Checker
Free GLP-1 drug interaction checker. Search any medication to see how it interacts with Wegovy, Ozempic, Zepbound, Mounjaro, or Foundayo.
Open tool →GLP-1 Injection-Site Rotation Calendar
Free injection-site rotation tracker for Wegovy, Ozempic, Zepbound, Mounjaro, and Saxenda. Log each weekly dose by site (abdomen, thigh, upper arm) and the tool returns the next recommended site per the FDA-label §2.3 rotation rule, with a printable rotation card you can keep on the fridge.
Open tool →GLP-1 Pre-Op Stop-Date Calendar
Free pre-surgery hold calendar for Wegovy, Ozempic, Zepbound, Mounjaro, Saxenda, Rybelsus, Foundayo, and compounded semaglutide / tirzepatide. Enter your surgery date and drug; the tool returns the last-safe-dose date and resume guidance per the ASA 2023 statement and the 2024 ASA / AGA / ASMBS / IPSO / SAGES multisociety update. Includes an 'I forgot to stop' recovery branch and a print-friendly summary patients can bring to their anesthesia team.
Open tool →GLP-1 Side Effect Timeline
When does each GLP-1 side effect peak and resolve? Interactive 6-drug x 7-side-effect x 5-week-bucket matrix. Every cell is anchored to an FDA label (DailyMed) or a pivotal-trial publication (STEP-1, STEP-4, SURMOUNT-1, SURMOUNT-5, SCALE, ATTAIN-1), with a verbatim primary-source quote on click.
Open tool →GLP-1 Vial & Pen Expiration Tracker
Free Beyond-Use-Date (BUD) tracker for Wegovy, Ozempic, Mounjaro, Zepbound, Saxenda, Rybelsus, Foundayo, and compounded semaglutide / tirzepatide. Enter your first-injection date and storage condition; the calculator returns the discard date per the FDA-approved label.
Open tool →GLP-1 Washout Calculator
How long does semaglutide, tirzepatide, orforglipron, or retatrutide stay in your system? Built on FDA-label half-life values.
Open tool →Pharmacy Legitimacy Lookup
Verify a compounding pharmacy against 5 public-record databases: FDA warning letters, openFDA drug recalls, Texas state pharmacy license database, Illinois IDFPR license registry, and the FDA 503B registered outsourcing facilities list. Primary-source disclosure rows — no AI score.
Open tool →Nutrition & lifestyle
Protein, fiber, water, and calorie targets while appetite is suppressed — plus how to pair training with a GLP-1.
Calorie Deficit Calculator
Free calorie deficit calculator. Enter your sex, age, height, weight, and activity level to get your BMR, maintenance calories (TDEE), and the daily calorie target for losing 0.5–2 lb per week — with a built-in 1,200/1,500 kcal safety floor.
Open tool →GLP-1 Exercise Pairing Configurator
Personalized weekly exercise template for patients on (or starting) a GLP-1 receptor agonist. Inputs your fitness level, age, goal, and time on the drug; outputs a research-backed weekly plan with resistance days, cardio minutes, step target, and protein guidance — all anchored on the S-LiTE trial, ACSM position stands, and the Neeland 2024 lean mass mitigation review.
Open tool →GLP-1 Fiber Calculator
Calculate your daily fiber goal while on a GLP-1 receptor agonist. Based on USDA Dietary Guidelines, adjusted for the constipation and GI side effects common with semaglutide and tirzepatide.
Open tool →GLP-1 Protein & Macro Calculator
Free protein and macro calculator for patients on (or starting) a GLP-1 receptor agonist. Anchored on PROT-AGE, Longland 2016, ISSN 2017, and the Neeland 2024 GLP-1 lean mass mitigation review.
Open tool →GLP-1 Water Intake Calculator
Calculate your daily water intake goal while on a GLP-1 medication. Accounts for body weight, activity level, climate, and the increased hydration needs caused by GLP-1 side effects like nausea and reduced appetite.
Open tool →Eligibility & expected results
Which drug fits, whether you meet the FDA label, and what the trial data predicts for your starting weight.
Bariatric Surgery Eligibility Checker
Eligibility under NIH 1991, ASMBS 2022, Medicare NCD 100.1, and 5 major commercial payers. Every payer entry traces to its published clinical policy bulletin.
Open tool →GLP-1 BMI Calculator
Free BMI calculator with a GLP-1 outcome overlay — current WHO BMI category, Wegovy/Zepbound FDA eligibility, and predicted BMI at each STEP-1, SURMOUNT-1, and ATTAIN-1 trial endpoint.
Open tool →GLP-1 Drug Decision Quiz
Multi-step decision engine that maps BMI, comorbidities, form preference, and special populations to the FDA-approved GLP-1 medication match — Wegovy, Zepbound, Mounjaro, Ozempic, Saxenda, Foundayo, or Rybelsus — with cited trial evidence (STEP, SURMOUNT, SELECT, FLOW, STEP-HFpEF, SURMOUNT-OSA, STEP-TEENS) at every branch.
Open tool →GLP-1 Weight Loss Calculator
Free interactive weight loss calculator backed by STEP-1 (semaglutide), SURMOUNT-1 (tirzepatide), and ATTAIN-1 (Foundayo) phase 3 trial data.
Open tool →Evidence lookups
Graded evidence for the supplements and non-GLP-1 medications readers ask about most.
Non-GLP-1 Drug Weight Effect Lookup
20 prescription drugs and their weight effects: metformin, topiramate, Qsymia, phentermine, Contrave, bupropion, Vyvanse, Adderall, Trulicity, Jardiance, Farxiga, spironolactone, HRT, sertraline, Lexapro, paroxetine, mirtazapine, vortioxetine, rosiglitazone, glyburide. Each entry verified against PubMed.
Open tool →Supplement Evidence Grader
16 popular weight-loss supplements graded A through D against verified PubMed primary sources. Search by name, filter by grade, see magnitude vs GLP-1 and the primary study citation for each entry.
Open tool →Editorial guides
Tools answer “how much” and “when”; the editorial guides answer “which drug,” “at what cost,” and “will my insurance cover it.”
These tools are educational and do not provide medical advice, diagnosis, or treatment recommendations. Dosing decisions should always be made with a qualified healthcare provider.
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