Calculators
Calculators for dose, cost and timing
38 tools for the arithmetic that sits either side of a GLP-1 purchase: how much drug is actually in the vial, when it clears, and what a year on each access path adds up to. Every input and source is listed on the tool page itself.
Milligrams are not units
Compounded semaglutide and tirzepatide are sold by vial concentration, so one prescribed dose is a different number of syringe units at 2.5 mg/mL than at 10 mg/mL. The converter and the reconstitution calculator exist because that is the step people get wrong.
A month is not a year
The advertised GLP-1 figure is often a first month, a prepay term or a membership fee. The savings calculator runs each path out to a year and to five, and it will report a higher total as readily as a lower one.
Every number has a source
Half-lives, titration schedules, fill volumes and side-effect windows come from FDA prescribing information on DailyMed or from the pivotal trial publications. Each page names what it used, so the math can be checked against the label rather than against us.
Filter 38 tools
Start here
Whether these drugs apply to you at all, before anything else.
GLP-1 Drug Decision Quiz
A branching decision engine. It takes BMI, comorbidities, whether you want an injection or a tablet, and any special-population factors, then works out which FDA-approved GLP-1 fits: Wegovy, Zepbound, Mounjaro, Ozempic, Saxenda, Foundayo or Rybelsus. Every branch names the trial behind it (STEP, SURMOUNT, SELECT, FLOW, STEP-HFpEF, SURMOUNT-OSA, STEP-TEENS).
GLP-1 BMI Calculator
BMI, plus what happens to it on treatment. Alongside your current WHO category it shows whether you meet FDA eligibility for Wegovy or Zepbound, and what your BMI becomes at the STEP-1, SURMOUNT-1 and ATTAIN-1 trial endpoints. Free.
Non-GLP-1 Drug Weight Effect Lookup
What twenty prescription drugs do to body weight. The antidepressants: sertraline, Lexapro, paroxetine, mirtazapine, vortioxetine. The diabetes and metabolic set: metformin, Trulicity, Jardiance, Farxiga, rosiglitazone, glyburide. The weight and stimulant group: Qsymia, topiramate, phentermine, Contrave, bupropion, Vyvanse, Adderall. Plus spironolactone and HRT. Every entry checked against PubMed.
Dose & titration
Converting units, reading a pen, planning a climb, and working out what a missed week does. Every schedule comes off the drug's own label.
GLP-1 Dose Plotter
A pharmacokinetic simulator you can play with. It charts how plasma concentration accumulates for four drugs (semaglutide, tirzepatide, orforglipron, retatrutide), drawing half-lives from the FDA labels and the published PK literature.
GLP-1 Pen Leftover Calculator
Tells you how many doses remain in an Ozempic or Saxenda multi-dose pen. The arithmetic comes from the fill volumes and dose counts printed in the FDA label. Free.
GLP-1 Unit Converter
Converts between milligrams and insulin-syringe units for compounded GLP-1 vials. Nothing but arithmetic, anchored to the FDA label.
GLP-1 Washout Calculator
Wondering how long semaglutide, tirzepatide, orforglipron or retatrutide sticks around after your last dose? This works it out from the half-life values in each FDA label.
GLP-1 Reconstitution Calculator
Handles the bacteriostatic-water, concentration and U-100 unit arithmetic for compounded GLP-1 vials. FDA maximum doses are enforced as hard limits, and the warnings follow ISMP conventions.
Mounjaro KwikPen Click & Dose Chart
Everything on the Mounjaro (tirzepatide) KwikPen in one place: all six strengths, the pen colors, how titration proceeds, storage, and how to administer it. Taken from the Mounjaro FDA prescribing information.
Zepbound KwikPen Dose Chart
The Zepbound KwikPen and every other Zepbound presentation in one place: all six strengths, four doses per KwikPen, how to prime and dial, in-use storage, the titration, injection steps, and LillyDirect self-pay prices. Taken from the Zepbound FDA label and Instructions for Use.
GLP-1 Reverse Dose Calculator (Units → mg)
Give it the units on your syringe and the concentration of your vial, and it tells you the milligram dose you are actually taking. Built for compounded semaglutide and tirzepatide, on the U-100 insulin syringe standard.
GLP-1 Split Dose Calculator
Splits a single weekly GLP-1 dose across two or three smaller injections, for anyone whose side effects land all at once. The syringe-unit arithmetic works at whatever concentration your vial happens to be.
GLP-1 Vial Transition Calculator
Your compounding pharmacy changed the concentration of your semaglutide or tirzepatide. This recalculates the units you should now draw. Getting this wrong is the most common dosing error with compounded GLP-1s.
GLP-1 Missed Dose Guide
Missed a dose? The answer differs by drug: Zepbound, Mounjaro, Foundayo, Wegovy and Ozempic each have their own rule. The guidance here is drug-specific and lifted straight from each drug's FDA prescribing information.
Brand-Switch Dose-Equivalence Calculator
Moving from Wegovy to Zepbound, or Foundayo to Saxenda, or any other pairing among the FDA-approved weight-loss GLP-1s. This lays out the §2 dose ladders from each label, the rules for re-titrating, and the caveats that apply when comparing across trials, for all four drugs. The point is that you arrive at the appointment already knowing.
GLP-1 Titration Schedule Planner
Lays out your escalation week by week for Wegovy, Ozempic, Zepbound, Mounjaro or Foundayo: start date, the date each dose step falls on, and reminders. The schedule follows the titration protocol in the FDA label.
Cost & coverage
What an access path costs over a year, and what your plan is likely to say about it.
GLP-1 Cost Per Pound Lost Calculator
Turns a monthly GLP-1 price into what each pound actually costs you, using loss figures from the STEP-1, SURMOUNT-1, ATTAIN-1 and SCALE trials. Free to use.
GLP-1 Prior Authorization Letter Generator
Assembles a prior-authorization letter for Wegovy, Zepbound, Saxenda or Foundayo, written in FDA-label language and carrying citations to the pivotal trials. Free.
GLP-1 Savings Calculator
Compare what you pay now against the alternative: brand Wegovy or Zepbound, compounded semaglutide or tirzepatide, and Foundayo. It reports the difference.
Insurance Employer Checker
Search by employer to see whether their plan covers GLP-1 weight-loss drugs. Each entry carries the metadata showing how and when it was verified.
State Medicaid GLP-1 Eligibility Pre-Screener
Check what your state's Medicaid program actually covers, across six indications: type 2 diabetes, obstructive sleep apnea, MASH/NASH, cardiovascular risk reduction, chronic weight management, and adolescents from 12. Every state gets a verbatim quote from the primary source, the date it was verified, how prior authorization works there, the appeal route, which PBM is involved, and a link through to the full write-up.
Skin-Removal Cost & Insurance Qualifier
A pre-screen for panniculectomy (CPT 15830), arm lift (15836) or thigh lift (15832) coverage after large weight loss. Enter your weight, how long it has held, how it came off and what a clinician has documented; it reads you against Aetna CPB 0211 and 0031, Cigna 0027 and 0470, and Anthem CG-SURG-99 and ANC.00009, and says where UnitedHealthcare's criteria cannot be read. Shows the ASPS average surgeon fee for arm and thigh lifts. Free.
Side effects & safety
When effects tend to appear, what interacts with what, and the dates surgery and storage depend on.
GLP-1 Vial & Pen Expiration Tracker
Beyond-Use-Date tracking for compounded semaglutide and tirzepatide, and for Zepbound, Mounjaro, Rybelsus, Saxenda, Foundayo, Wegovy and Ozempic. Tell it when you first injected and how the vial or pen is being stored; it returns the discard date the FDA-approved label specifies. No charge.
GLP-1 Drug Interaction Checker
Type in any medication and see how it behaves alongside Wegovy, Ozempic, Zepbound, Mounjaro or Foundayo. Free, no sign-up.
GLP-1 Side Effect Timeline
Shows when a given side effect tends to peak and when it settles. Six drugs against seven side effects across five week-buckets, and every cell traces to either an FDA label on DailyMed or a pivotal trial publication (STEP-1, STEP-4, SURMOUNT-1, SURMOUNT-5, SCALE, ATTAIN-1). Click a cell for the quote itself.
GLP-1 Pre-Op Stop-Date Calendar
Surgery coming up? Enter the date and your drug (Wegovy, Ozempic, Zepbound, Mounjaro, Saxenda, Rybelsus, Foundayo, or compounded semaglutide or tirzepatide) and this returns the last date you can safely dose, plus when to restart. It follows the ASA 2023 statement and the 2024 multisociety update from ASA, AGA, ASMBS, IPSO and SAGES. There is a branch for people who have already forgotten to stop, and a printable summary for your anesthesia team. Free.
GLP-1 Injection-Site Rotation Calendar
Log each weekly dose against where you injected it, abdomen, thigh or upper arm, and this tells you where the next one goes under the rotation rule in §2.3 of the FDA label. Covers Wegovy, Ozempic, Zepbound, Mounjaro and Saxenda, and prints a card for the fridge. Free.
Food, training & results
Protein, fiber, fluid and calories against a shrinking appetite — and what the trials say to expect on the scale.
Calorie Deficit Calculator
Work out a daily calorie target without paying for anything. Give it sex, age, height, weight and how active you are; back come your BMR, your maintenance figure (TDEE) and the intake that produces 0.5 to 2 lb of loss a week. A 1,200/1,500 kcal floor is built in and cannot be overridden.
GLP-1 Weight Loss Calculator
Projects loss over time from the phase 3 data itself: STEP-1 for semaglutide, SURMOUNT-1 for tirzepatide, ATTAIN-1 for Foundayo. Interactive and free.
GLP-1 Protein & Macro Calculator
Protein and macro targets for anyone on a GLP-1 receptor agonist or about to start one. The numbers rest on PROT-AGE, Longland 2016, the ISSN 2017 position stand, and Neeland's 2024 review of lean-mass mitigation. Free.
GLP-1 Exercise Pairing Configurator
Builds a week of training around your GLP-1 treatment. Feed it your fitness level, age, goal and how long you have been on the drug; back come cardio minutes, resistance days, a step target and protein guidance. Behind the programming sit ACSM position stands, the S-LiTE trial, and Neeland's 2024 review of lean mass.
GLP-1 Water Intake Calculator
Sets a daily hydration target for someone on a GLP-1, factoring in body weight, activity, climate, and the extra fluid you need when nausea and a blunted appetite are already reducing what you take in.
GLP-1 Fiber Calculator
Sets a daily fiber target for someone on a GLP-1 receptor agonist. It starts from the USDA Dietary Guidelines and adjusts upward for the constipation and gut symptoms that come with semaglutide and tirzepatide.
Check a product or seller
Read a vial label, check a pharmacy's licensing, and grade the evidence behind what you were sold.
GLP-1 Vial Label Reader
Tap a field on a compounded semaglutide or tirzepatide label and it explains what that field means: concentration, bacteriostatic water, units against milligrams, the BUD. A calculator underneath converts your own label into the exact number of units to draw.
Supplement Evidence Grader
Sixteen weight-loss supplements, each graded A to D against primary sources indexed in PubMed. Search by name or filter by grade to see how the effect size compares with a GLP-1 and which study the grade rests on.
Pharmacy Legitimacy Lookup
Runs a compounding pharmacy against five public records: FDA warning letters, openFDA recalls, the Texas state pharmacy license database, the Illinois IDFPR registry, and the FDA's list of registered 503B outsourcing facilities. What comes back is the disclosure rows themselves. There is no score and no algorithm.
Peptides
Reconstitution and unit math for peptides, plus what each one's regulatory and evidence standing actually is.
Peptide Reconstitution Calculator
Peptides are prescribed in micrograms and drawn on a syringe marked in units, and nothing on the vial converts between them. Give it the milligrams in the vial, the bacteriostatic water you are adding and the prescribed dose; back come the concentration, the volume, the syringe units and how many doses the vial holds. Warns when a draw is too small to measure or will not fit.
Peptide Status Checker
Two questions decide most of what matters before buying a peptide: can a licensed US pharmacy legally supply it, and has anyone tested it in people for the use it is sold for. This gives both answers for every peptide we track, with the evidence graded A to D.
Longer reference pages
The calculators handle the arithmetic. These pages handle the parts that have to be read: which drug the label actually covers, what each channel is charging this month, and what an insurer will and will not pay for.
Nothing here is medical advice, a diagnosis, or a treatment recommendation. These pages are arithmetic and citations. Any change to a dose belongs with a licensed clinician who knows your history.
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CoreAge Rx
Semaglutide at $99/month, 48% below the typical price
From $99/mo
Get started →Trimi Health
Knowing which pharmacy fills the vial: it names VialsRx
From $99/mo
Get started →ShedRx
Oral orforglipron alongside the injectables
From $149/mo
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