Posted May 6, 2026 · PeptideCase Editorial
Mixing peptides at home is mostly arithmetic. The math is simple — vial mg ÷ BAC water mL = concentration. But doing it right at 11 PM on a Sunday after a long day is how mistakes happen. That's why we partner with two free online calculators that handle the math for you: GLP1Calculator.com for standard weekly dosing, and GLP1Microdose.com for split-dose protocols.
This article walks through how to use both, when to use which, and why the case you store your reconstituted vials in matters more than most people think.
The Reconstitution Formula (Universal)
Every peptide reconstitution follows the same three-step math:
- Concentration = vial mg ÷ BAC water mL
- Injection volume = your dose ÷ concentration
- Syringe units (U100) = injection volume × 100
Example: 5 mg semaglutide vial + 2 mL BAC water = 2.5 mg/mL concentration. For a 0.5 mg dose: 0.5 ÷ 2.5 = 0.2 mL = 20 units on a U100 syringe.
Simple — but easy to mess up if you're tired, doing it for the first time, or switching compounds. Both of our partner calculators handle this instantly.
When to Use the Standard Calculator
The GLP1Calculator Reconstitution tool is ideal for:
- Standard weekly GLP-1 protocols (Ozempic, Wegovy, Mounjaro, Zepbound, compound versions)
- BPC-157, TB-500, CJC-1295/Ipamorelin and other research peptides
- Anyone using the manufacturer-recommended titration schedule
- First-time reconstituters who want clear visual feedback (the calculator shows a syringe diagram with a "fill to here" indicator)
When to Use the Microdose Calculator
The GLP1Microdose Calculator is built for split-dose protocols. Microdosing means injecting smaller, more frequent doses (2x/week, 3x/week, or daily) instead of one big weekly shot. Reasons people microdose:
- Fewer side effects. Lower peak concentrations = less nausea, GI distress, fatigue
- Smoother appetite suppression. Stable plasma levels = consistent satiety throughout the week
- Maintenance dosing after reaching goal weight (microdoses are perfect for staying lean without re-escalating)
- Retatrutide protocols — the most potent GLP-1 — where most users microdose to manage side effects
The microdose calculator adds a frequency selector (1x/2x/3x weekly or daily) and computes your weekly equivalent so you can compare to a standard dose. It also handles smaller dose increments — you can plug in 0.05 mg microdoses, which the standard calculator wouldn't typically need.
Standard vs Microdose — Quick Reference
| Compound | Standard weekly | Microdose (2x/wk) | Microdose (daily) |
|---|---|---|---|
| Semaglutide | 0.25 – 2.4 mg | 0.125 – 1.2 mg | 0.04 – 0.34 mg |
| Tirzepatide | 2.5 – 15 mg | 1.25 – 7.5 mg | 0.36 – 2.14 mg |
| Retatrutide | 1 – 12 mg | 0.5 – 6 mg | 0.14 – 1.71 mg |
These are reference ranges, not prescriptions. Always work with a licensed healthcare provider — and always run the math through the calculator to get your exact mL and syringe units before drawing a dose.
Storage Matters as Much as the Math
Once you've reconstituted a vial, the math is done — but the work is just starting. Reconstituted GLP-1 peptides are sensitive: refrigerate them at 36-46°F (2-8°C), protect from light, never freeze, and use within 28 days.
This is where storage cases become critical. If you're microdosing, you'll have more vials in active rotation at any given time (because each vial lasts longer when you take less per dose). A purpose-built case keeps them organized, upright, and protected from breakage.
For both standard dosers and microdosers, the cases that fit our community best are 3ml peptide vial cases with integrated BAC water and syringe storage. Our most popular options:
The Workflow That Works
Here's the full reconstitution-to-injection workflow we recommend:
- Plan your dose with the calculator. Standard weekly: glp1calculator.com/reconstitution. Microdose: glp1microdose.com/calculator
- Mix following our reconstitution guide. Slow injection of BAC water down the glass wall, gentle swirl, no shaking
- Refrigerate immediately in a hard-shell case at 36-46°F
- Draw to the exact unit mark shown by the calculator's syringe fill guide
- Inject subcutaneously — abdomen, thigh, or upper arm
- Track your dose with our level plotter to see your plasma accumulation
Bottom Line
Reconstitution math is universal but tedious. Use the right calculator for your protocol — GLP1Calculator for standard weekly dosing, GLP1Microdose for split-dose protocols. Then store the result correctly in a purpose-built case. Your peptides last longer, work better, and don't end up in the trash from breakage or contamination.