GLP-1 Dose Calculator for Semaglutide & Tirzepatide

Calculate exact doses for compounded Semaglutide and Tirzepatide.

SemaglutideTirzepatideRetatrutideCompounded GLP-1s

Peptide Reconstitution Calculator

Calculate your exact dose

Enter your vial details to calculate how many units to draw for your dose.

Common doses: Semaglutide (0.25-2.4mg), Tirzepatide (2.5-15mg)

Draw syringe to

100 units

(1.00 mL)

0204060801001030507090▼ 100 units
Your dose (2.5mg)
100 units = 1mL

Concentration:

2,500 mcg/mL

Doses per vial:

2

Your reconstitution is set — now track your protocol.

Regimen logs every dose of your peptide — 2.5mg at a time, 2 doses per vial. It reminds you when to inject, tracks your reconstitution dates, and manages multi-compound schedules.

  • Injection reminders for each compound
  • Track reconstitution dates and vial expiry
  • Manage multiple peptides on different schedules

Free for one compound. No trial, no paywall.

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For educational and research purposes only. This calculator provides estimates based on standard formulas.

Always verify calculations with your healthcare provider before use. We assume no liability for dosing errors, adverse events, or outcomes resulting from use of this tool.

How to Use This Calculator

1

Enter vial size

The mg amount on your GLP-1 vial (e.g., 5mg, 10mg)

2

Enter BAC water

How much bacteriostatic water you added (typically 2mL)

3

Enter weekly dose

Your target dose in mg (e.g., 0.25mg, 0.5mg, 2.5mg)

4

Read your result

See exactly how many units to draw on your syringe

How to Calculate Your GLP-1 Injection Dose

If you're using compounded semaglutide or tirzepatide (not pre-filled pens like Ozempic or Mounjaro), you need to calculate how many units to draw on your insulin syringe based on your vial's concentration and your prescribed dose.

The formula:

Units to draw = Prescribed dose (mg) ÷ Concentration (mg/mL) x 100

Example: Your compounded semaglutide is 5mg/2mL (2.5mg/mL). Your prescribed dose is 0.25mg.

0.25 ÷ 2.5 x 100 = 10 units

Semaglutide Titration Schedule

Semaglutide is typically titrated (gradually increased) to reduce side effects. Here's the standard titration:

WeekWeekly DosePurpose
Weeks 1-40.25mgStarting dose, let your body adjust
Weeks 5-80.5mgFirst increase
Weeks 9-121.0mgSecond increase
Weeks 13-161.7mgThird increase (Wegovy protocol)
Week 17+2.4mgMaintenance dose (Wegovy protocol)

Your provider may adjust this schedule based on your response and tolerance. Use the calculator above to recalculate your syringe units at each dose increase. Regimen's GLP-1 titration planner maps out your full titration schedule with dates.

Tirzepatide Titration Schedule

WeekWeekly DosePurpose
Weeks 1-42.5mgStarting dose
Weeks 5-85mgFirst increase
Weeks 9-127.5mgSecond increase
Weeks 13-1610mgThird increase
Weeks 17-2012.5mgFourth increase
Week 21+15mgMaximum dose

Titrate only when your provider recommends it. Not everyone reaches the maximum dose.

Track Your GLP-1 Progress

Calculating your dose is step one. Tracking whether it's working is step two.

1

Log every injection

in Regimen — dose, timing, and injection site.

2

Track your weight and body fat

automatically through Apple Health or Google Health Connect.

3

Monitor side effects

over time — see if nausea decreases as your body adjusts to each dose level.

4

Visualize your medication levels

between weekly injections with Regimen's half-life visualizer.

Example GLP-1 Calculations

Common dosing scenarios for compounded semaglutide and tirzepatide

Semaglutide
Vial:5mg
Water:2mL
Weekly dose:0.5mg
20 units
10 weeks per vial
Tirzepatide
Vial:10mg
Water:2mL
Weekly dose:2.5mg
50 units
4 weeks per vial
Semaglutide
Vial:10mg
Water:3mL
Weekly dose:1mg
30 units
10 weeks per vial

What This GLP-1 Calculator Does

This calculator is designed for compounded versions of GLP-1 receptor agonists — the kind that come as lyophilized powder in vials rather than pre-filled pens. If you're using compounded semaglutide (the active ingredient in Ozempic and Wegovy) or compounded tirzepatide (Mounjaro and Zepbound), you need to reconstitute the powder with bacteriostatic water before injecting.

Enter your vial size, how much BAC water you added, and your prescribed dose. The calculator converts your dose into exact insulin syringe units so you draw the right amount every time. It also works for retatrutide and other emerging GLP-1 compounds.

Need help building a dose escalation timeline? Learn more in our GLP-1 tracker guide

GLP-1 Dosing Questions

Data Sources

This tool uses dosing information from official prescribing information:

  • Reconstitution Math — Standard concentration and volume calculations for peptide reconstitution
  • GLP-1 Dosing Guidelines — Typical titration schedules for semaglutide and tirzepatide
  • Insulin Syringe Standards — U-100 syringe conversion: 100 units = 1mL

Track your GLP-1 journey

Regimen has a built-in dose calculator plus weekly reminders, weight tracking, and progress photos.

  • Built-in dose calculator
  • Weekly injection reminders
  • Track weight over time
  • Progress photo timeline
Regimen app screenshot showing protocol tracking