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Vial longevity

Vial Longevity & Runway Calculator

Calculate how many days and weeks a reconstituted vial will last based on your dosing protocol and monitor BAC water shelf life limits.

01Inputs
02The answer
Vial Duration
20days
~2.9 weeks
Total Doses in Vial
20.0doses
5 mg total
Estimated Months
0.7months
At current schedule
BAC Water Status
Safe<28 days
Reconstitution shelf life
03How this works

Vial Runway Math & Potency Protection

Written out so you can check it by hand. The app runs this exact function, not a second implementation that drifts.

Vial longevity calculates the runway of a reconstituted vial given your specific dosing schedule.

1. Total Doses per Vial: Total Doses = Total Content (mg) ÷ Dose Amount (mg).

2. Duration in Days: Days Lasting = (Total Doses × 7) ÷ Weekly Dose Count. At 7 doses per week (daily), 20 doses will last 20 days.

3. Bacteriostatic Water Limit: Once reconstituted, 28 days is the recommended maximum duration for multi-dose vials stored at 2–8°C.

04Questions
Why is there a 28-day shelf life warning on reconstituted vials?
Bacteriostatic Water uses 0.9% benzyl alcohol as a preservative. Once a vial rubber stopper is multi-punctured, USP <797> guidelines recommend discarding multi-dose vials within 28 days to minimize microbial contamination risk and potency degradation.
How do I calculate total doses per vial?
Total Doses = Total Vial Content (in mg or mcg) divided by Single Target Dose (in the same unit). For example, a 5 mg (5,000 mcg) vial divided by 250 mcg per dose yields 20 total doses.
What is the most common vial-runway mistake?
Counting doses in one unit and dosing in another: a 5 mg vial at 250 mcg per dose is 20 doses, not 50. The second is forgetting that the 28-day discard window can run out before the contents do: actual runway is the smaller of doses-remaining and days-remaining, and this calculator warns when the math outruns the window.
Should I freeze reconstituted peptide vials to extend shelf life?
No. Repeated freeze-thaw cycles can break fragile peptide bonds and denature tertiary protein structures. Store reconstituted vials refrigerated at 2–8°C (36–46°F) and do not freeze liquid solutions.
05Related calculators
ReconstitutionVial size and BAC water in, concentration and syringe units out, with a visual fill indicator.Half-lifeHow much of a compound remains after a given interval, and when it settles at steady state.Cost per doseVial price against doses per vial, so suppliers compare on the number that matters.Unit converterIU, mcg and mg in both directions, including insulin-syringe units.GLP-1 titrationLay a titration schedule against real dates and see the whole ramp at once.

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