GLP-1 · RECONSTITUTION

Semaglutide dosage calculator

Semaglutide dosage calculator with reconstitution math for 2mg, 5mg, and 10mg lyophilized vials. Full 0.25 → 2.4mg titration schedule, live U-100 insulin syringe draw, and the compounded vs branded comparison.

Using the calculator

How to use this Semaglutide dosage calculator

This Semaglutide dosage calculator runs reconstitution math live for the research-format Semaglutide vial sizes — 2mg, 5mg, and 10mg lyophilized vials — and returns the exact mark to draw to on a 1mL U-100 insulin syringe. The defaults above (5mg vial, 2mL bacteriostatic water, 0.25mg target dose) match a common starting-titration protocol and pull to the 10-unit mark on a U-100 syringe — the same 0.25mg dose delivered by a Week-1 Ozempic pen, just drawn from a research vial instead of pre-filled.

Pick your Semaglutide vial size

Research-format compounded Semaglutide ships in 2mg, 5mg, or 10mg lyophilized vials — the supplier presets above cover all three. The 5mg vial is the most common starting format because it cleanly yields a 30-day supply at the standard titration doses. The 10mg vial extends coverage for users already titrated to 2mg+ weekly maintenance.

Pick your BAC water volume

Semaglutide reconstitutes cleanly at 2mL of bacteriostatic water for a 5mg vial — a 2.5 mg/mL concentration where 0.25mg pulls to 10U, 1mg pulls to 40U, and 2mg pulls to 80U on a U-100 syringe. The 10mg vial reconstituted with 2mL yields 5 mg/mL (halves every draw). Lower BAC volumes produce hard-to-read marks at the low starting doses.

Set your Semaglutide target dose

Semaglutide is dosed in milligrams — switch the unit toggle to mg. The standard titration schedule is 0.25 mg weekly for 4 weeks, then 0.5 mg, then 1.0 mg, then 1.7 mg, then 2.4 mg — the full Wegovy weight-loss titration or the identical Ozempic diabetes schedule (capped at 2.0 mg). Enter your current titration dose and the calculator returns U-100 units, injection volume, concentration, and doses per vial.

Read the U-100 syringe units

Pull the plunger to the indicated unit mark on a 1mL U-100 insulin syringe. At default settings (5mg/2mL/0.25mg dose), the draw is 10U — same total active peptide as a Week-1 branded pen click. The visual syringe above shows the fill in real time — drag it directly to scrub through titration steps live.

PEPTIDEMAXXERS · IOS · IPADOS

The full protocol in your pocket.

Reconstitution math is step one. Running a peptide protocol means reminders, rotation, adherence, and history. PeptideMaxxers handles all of it — offline-first, privacy-first, native SwiftUI.

Download on the
App Store
iOS 17+ · 12 MB · ★ 4.9
Dose logging
One-tap injection logs with site, time, note.
Cycle scheduling
Titrations, alternating cadences, split dosing.
Push reminders
Exact draw (e.g. 25U on U-100) right in the banner.
HealthKit sync
Mirror doses into Apple Health automatically.
Adherence streaks
12-week streak grid — see your consistency.
iCloud backup
Protocols and logs sync across iPhone + iPad.
PeptideMaxxers iOS app — onboarding screen with reconstitution math preview
PeptideMaxxers iOS app — peptide library showing 23 compounds with categories and half-life
PeptideMaxxers iOS app — Tirzepatide dose logged confirmation
WEB CALCULATOR · VS · PEPTIDEMAXXERS APP

This calculator handles the math. The app handles the protocol.

FEATURE
WEB · FREE
APP · $
Real-time reconstitution math
23-compound preset library
Visual U-100 syringe
Dose logging + injection history
Injection-site rotation tracking
Cycle / protocol scheduler
Push reminders before every dose
HealthKit sync
Offline + iCloud backup
Adherence analytics + streaks
STILL ON THE FENCE?
Run your full Semaglutide protocol in the app — dose logs, site rotation, reminders, cycle tracking.
Download on the
App Store
Complete reference · Semaglutide

Semaglutide dosage, reconstitution, and titration guide

Semaglutide is a GLP-1 receptor agonist developed by Novo Nordisk and marketed as Ozempic® (type 2 diabetes, up to 2.0 mg weekly) and Wegovy® (chronic weight management, up to 2.4 mg weekly). Both are FDA-approved pre-filled pens delivering the same molecule at different max doses. Research-format compounded Semaglutide is the same peptide in lyophilized vial form, available through licensed 503A compounding pharmacies under the FDA's ongoing shortage safe-harbor framework (capped at ≤4 prescriptions per month per patient as of the February 2025 resolution guidance). This guide covers Semaglutide dose math, the full titration schedule, reconstitution at 2mg / 5mg / 10mg vial sizes, dosing in units vs mg, compounded vs branded differences, side effects, max-dose protocols, and the Semaglutide vs Tirzepatide comparison.

Semaglutide dosing schedule and titration

Semaglutide uses a strict stepwise titration to manage gastrointestinal tolerability — primarily nausea, which is the dose-limiting side effect. The schedule below matches the FDA-approved titration for Wegovy (weight loss) and is identical through 2.0 mg for Ozempic (diabetes, which caps at 2.0 mg). Doses are the standard clinical schedule, not medical recommendations.

Titration weekWeekly doseU-100 units (5mg/2mL vial)Notes
Weeks 1–40.25 mg10UInitiation — tolerability assessment
Weeks 5–80.5 mg20UFirst full titration step
Weeks 9–121.0 mg40UOzempic standard maintenance
Weeks 13–161.7 mg68UWegovy titration step
Weeks 17+2.0 mg80UOzempic max dose (diabetes)
Weeks 17+ (Wegovy)2.4 mg96UWegovy max dose (weight loss)

Semaglutide reconstitution — 2mg, 5mg, 10mg vials

The 5mg lyophilized vial is the most common research Semaglutide format. Reconstitution at 2mL of bacteriostatic water yields a 2.5 mg/mL concentration — the standard working concentration where every titration step pulls to a clean U-100 mark (0.25mg = 10U, 0.5mg = 20U, 1mg = 40U, 2mg = 80U, 2.4mg = 96U). The 2mg vial with 1mL BAC yields 2 mg/mL. The 10mg vial with 2mL BAC yields 5 mg/mL (halves every draw — useful for users already at 2mg+ maintenance).

STEP 01
Bring vial to room temperature
Lyophilized Semaglutide ships cold. Allow 10–15 minutes at room temperature before reconstitution.
STEP 02
Wipe both stoppers with alcohol
Both the Semaglutide vial and the bacteriostatic water vial.
STEP 03
Draw 2mL of BAC water
Use a 3mL drawing syringe with 18–21G needle. 2mL is the standard volume for a 5mg vial.
STEP 04
Inject BAC slowly down the vial wall
Tilt the Semaglutide vial and inject the bacteriostatic water down the inside wall — never directly onto the lyophilized cake.
STEP 05
Swirl gently until clear
Swirl 30–60 seconds. Semaglutide dissolves to a clear, slightly viscous solution. Do not shake — Semaglutide is a 31-amino-acid modified peptide and aggressive agitation can affect potency.
STEP 06
Refrigerate
Store at 2–8°C. Reconstituted Semaglutide is stable for approximately 4–6 weeks refrigerated — longer than most research peptides due to Semaglutide's inherent molecular stability (the same stability that allows Ozempic pens to ship at room temperature for up to 56 days).
STEP 07
Draw weekly dose with U-100 syringe
Semaglutide is dosed once weekly. For a 5mg/2mL vial at 0.25mg starting dose: draw to 10U. Inject subcutaneously in abdomen, thigh, or upper arm.

Semaglutide dose in units — U-100 syringe reference

Users switching from branded Ozempic or Wegovy pens to research vials often ask how to convert "clicks" to units. Pens deliver a fixed volume per click (~0.74 mL per dose at Ozempic's 1 mg concentration), which translates to a specific mg dose. With research vials and U-100 syringes, you measure in units. The conversion depends entirely on your reconstitution concentration. At the standard 2.5 mg/mL (5mg vial + 2mL BAC water), the unit marks line up cleanly: every 0.25mg = 10 units. Above, the calculator computes this live for any vial/BAC combination.

Compounded Semaglutide vs Ozempic vs Wegovy

All three contain the same active peptide — semaglutide — but differ in regulatory status, presentation, and maximum dose. Ozempic® is Novo Nordisk's FDA-approved pre-filled pen for type 2 diabetes, available at 0.25, 0.5, 1.0, and 2.0 mg weekly doses. Wegovy® is the identical molecule in a pre-filled pen FDA-approved for chronic weight management, available at the full 0.25 → 2.4 mg titration. Compounded Semaglutide is the same peptide in lyophilized vial form, prepared by licensed 503A compounding pharmacies and dispensed by prescription. Under the FDA's February 2025 shortage-resolution guidance, 503A compounding is capped at ≤4 prescriptions per month per patient. Compounded versions are chemically equivalent when sourced from reputable pharmacies but lack the pen delivery system and require manual reconstitution and U-100 syringe draws.

Semaglutide for weight loss vs type 2 diabetes

The underlying mechanism is identical across indications. For type 2 diabetes (Ozempic labeling), semaglutide is dosed up to 2.0 mg weekly and produces 5–10% weight loss as a secondary effect alongside primary glucose control. For chronic weight management (Wegovy labeling), semaglutide is dosed up to 2.4 mg weekly and produces 14–16% mean body weight reduction over 68 weeks in clinical trials (STEP-1 study). The higher Wegovy dose is the only meaningful pharmacological difference — everything else (molecule, delivery, titration pattern through 1.7 mg) is identical. Users running research protocols can select their target dose based on their goal: 1.0–2.0 mg for glucose-control research, 2.4 mg for maximum weight-loss effect.

Semaglutide side effects

Side effects are overwhelmingly gastrointestinal and are the reason the titration schedule exists. Nausea is the most common adverse event, peaks during titration steps, and partially adapts during maintenance. Slow titration and eating lighter meals for 24–48 hours after each injection reduce severity. Vomiting and diarrhea occur in a minority and are more frequent at 2.0+ mg doses. Constipation is common at all dose levels. Decreased appetite is the intended therapeutic effect and is universal. Mild heart rate elevation (~3–5 bpm) is observed clinically. Rare but serious: pancreatitis risk (most relevant for users with a personal or family history), medullary thyroid carcinoma (boxed warning — contraindicated with MEN2 or personal/family history of MTC), gallbladder disease during rapid weight loss. Injection-site reactions are minimal compared to other subcutaneous peptides.

Semaglutide vs Tirzepatide

Semaglutide and Tirzepatide are the two most widely used incretin-mimetic peptides, but they differ mechanistically. Semaglutide is a GLP-1 receptor monoagonist — it activates only the GLP-1 pathway. Tirzepatide (Mounjaro/Zepbound) is a dual agonist activating both GLP-1 and GIP receptors. In head-to-head clinical data (SURMOUNT-1 vs STEP-1), Tirzepatide 15 mg produced ~21% body weight reduction at 72 weeks vs Semaglutide 2.4 mg's ~15% at 68 weeks. Both use weekly subcutaneous injection with similar titration logic. Semaglutide has longer real-world use, more cardiovascular outcomes data (SELECT trial showed 20% reduction in major cardiovascular events), and is typically less expensive. Tirzepatide produces larger weight-loss effect and often better glycemic control. Users running research protocols can calculate dosing for either compound on the /tirzepatide/ or /semaglutide/ calculators.

How long can you take Semaglutide?

Unlike research peptides that are conventionally cycled (BPC-157 on/off, Tesamorelin 12–16 week cycles), Semaglutide is designed for continuous long-term use. Clinical trials run 68 weeks (STEP-1, Wegovy) or longer (SUSTAIN-6, diabetes outcomes). Discontinuation consistently produces weight regain — roughly two-thirds of lost weight within 12 months of stopping per the STEP-4 extension study — which is why clinical guidance treats semaglutide as chronic therapy for chronic disease. There is no documented tolerance or receptor desensitization at standard doses; continuous weekly dosing maintains efficacy indefinitely.

Frequently asked questions

What is the standard Semaglutide dose?
Semaglutide uses a titration schedule: 0.25 mg weekly for 4 weeks, then 0.5 mg for 4 weeks, then 1.0 mg for 4 weeks, then 1.7 mg for 4 weeks, then 2.4 mg weekly maintenance (Wegovy weight-loss labeling). The Ozempic diabetes labeling uses the same schedule but caps at 2.0 mg. All doses are given once weekly by subcutaneous injection.
How do you calculate a Semaglutide dose?
Semaglutide dose calculation uses the standard peptide reconstitution math: concentration (mg/mL) = vial mg ÷ BAC mL; injection volume (mL) = dose mg ÷ concentration; U-100 syringe units = injection volume × 100. For a 5mg vial reconstituted with 2mL of BAC water and a 0.25mg starting dose: concentration is 2.5 mg/mL, injection volume is 0.1 mL, draw to 10 units on a U-100 syringe.
How much bacteriostatic water do I add to a 5mg Semaglutide vial?
2mL of bacteriostatic water is the standard reconstitution volume for a 5mg Semaglutide vial. This yields a 2.5 mg/mL concentration where every titration step pulls to a clean U-100 mark (0.25mg = 10U, 0.5mg = 20U, 1mg = 40U, 2mg = 80U, 2.4mg = 96U).
How many units is 0.25mg of Semaglutide?
It depends on concentration. For a 5mg vial reconstituted with 2mL BAC water (2.5 mg/mL): 0.25mg pulls to 10 units on a U-100 syringe — the same active peptide amount as a Week-1 Ozempic or Wegovy pen click. For a 10mg vial with 2mL BAC (5 mg/mL): 5 units. The calculator above computes this live.
How many units is 1mg of Semaglutide?
For a 5mg vial reconstituted with 2mL BAC water (2.5 mg/mL): 1mg pulls to 40 units on a U-100 syringe. For a 10mg vial with 2mL BAC (5 mg/mL): 20 units. For a 2mg vial with 1mL BAC (2 mg/mL): 50 units.
What is the difference between compounded Semaglutide and Ozempic?
Both contain the same active peptide. Ozempic® is Novo Nordisk's FDA-approved pre-filled pen (up to 2.0 mg weekly, approved for type 2 diabetes). Compounded Semaglutide is the same molecule in lyophilized vial form, prepared by licensed 503A compounding pharmacies under the FDA's shortage safe-harbor framework (capped at ≤4 prescriptions per month per patient as of February 2025). Compounded versions require manual reconstitution and U-100 syringe draws rather than pen delivery.
When should you inject Semaglutide?
Once weekly, any day, with or without food. Most users pick a consistent weekly injection day and time. Semaglutide's ~7-day half-life allows flexible timing within a roughly 48-hour window without clinical impact. Injection sites rotate between abdomen, thigh, and upper arm.
What is the Semaglutide half-life?
Semaglutide has a serum half-life of approximately 165–184 hours (about 7 days) — one of the longest of any peptide on this calculator. The extended half-life is engineered via a fatty acid chain that binds albumin and slows renal clearance. This is why Semaglutide is dosed once weekly rather than daily.
What are Semaglutide side effects?
The most common are gastrointestinal: nausea (peaks during titration), vomiting, diarrhea, constipation, and decreased appetite (intended). Mild heart rate elevation (~3–5 bpm) is observed. Rare but serious risks include pancreatitis (relevant for users with pancreatitis history) and a boxed warning for medullary thyroid carcinoma (contraindicated with MEN2 or personal/family history of MTC). Slow titration significantly reduces GI side effects.
How much weight do you lose on Semaglutide?
Clinical trial data: STEP-1 (Wegovy 2.4 mg) produced 14.9% mean body weight reduction at 68 weeks. Ozempic labeling (up to 2.0 mg for diabetes) typically produces 5–10% weight loss as a secondary effect. Individual results vary with adherence, dose, diet, exercise, and baseline weight.
Can you take Semaglutide long-term?
Yes — Semaglutide is designed for chronic continuous use, not cycled like research peptides. Clinical trials run 68+ weeks. Discontinuation produces weight regain (approximately two-thirds of lost weight within 12 months per the STEP-4 extension). There is no documented tolerance or receptor desensitization at standard doses. Current clinical guidance treats Semaglutide as ongoing chronic therapy.
What is the difference between Semaglutide and Tirzepatide?
Semaglutide is a GLP-1 receptor monoagonist. Tirzepatide is a dual GLP-1 + GIP receptor agonist. In head-to-head clinical data, Tirzepatide 15 mg produces ~21% body weight reduction at 72 weeks vs Semaglutide 2.4 mg's ~15% at 68 weeks. Both use weekly subQ injection. Semaglutide has more cardiovascular outcomes data (SELECT trial: 20% reduction in major cardiovascular events); Tirzepatide produces a larger weight-loss effect.
RESEARCH USE ONLY. This calculator and the information on this page are provided for informational and research purposes only. Consult a licensed medical provider before administering any peptide. PeptideMaxxers does not manufacture, sell, or ship peptides. Doses, cycle lengths, and protocols referenced above are common values from published research and community sources — they are not medical recommendations.