Vial Duration
Estimator
Enter your vial strength, your dose per injection, and how often you inject. See how many doses the vial holds, how long it lasts, and roughly when you'll run out.
Your supply
One vial lasts
≈ 2.9 weeks · 20 doses per vial
How this works
Methodology reviewed July 2026The number of doses in a vial is fixed by arithmetic: the total peptide mass in micrograms (vial strength in mg × 1000) divided by the dose per injection in micrograms. How long that supply lasts depends only on how many doses you take per week — the tool converts your chosen frequency into doses per week, divides the dose count by it, and multiplies by seven to express the result in days. The bacteriostatic water you add changes the concentration and the volume you draw, but never the peptide mass, so it has no effect on the dose count or the vial's lifespan. The estimated run-out date simply adds the total supply, in days, across all vials on hand to today's date in your browser.
doses_per_vial = (vial_strength_mg × 1000) / dose_mcg
doses_per_week = frequency (e.g. once daily = 7, weekly = 1)
days_per_vial = doses_per_vial / (doses_per_week / 7)
total_supply_days = days_per_vial × vials_on_hand
Vial strength (mg) · Dose per injection (mcg or mg) · Dosing frequency · Vials on hand
Doses per vial · Days one vial lasts · Total supply duration · Estimated run-out date
- Every dose drawn is the same size, and none of the vial is wasted to dead space, priming, or spillage.
- The vial is labeled accurately — the calculation is only as correct as the milligram figure you enter.
- All vials on hand are identical in strength and are used at the same frequency.
- Doses per vial depend only on vial strength and dose size, not on how much bacteriostatic water was added.
- This is supply arithmetic only; it does not judge whether a dose or frequency is safe, effective, or appropriate for any purpose.
- Real-world yield is usually slightly lower than the theoretical dose count because of dead space in the needle, adsorption to the vial, and the last unusable fraction of a draw.
- The run-out date is a simple projection from today and does not account for missed doses, schedule changes, or reconstituted-vial stability limits.
- It does not track beyond-use dating — a reconstituted vial has a limited shelf life regardless of how many doses remain.
- Watch the units — micrograms (mcg) and milligrams (mg) are a thousand-fold apart, and mixing them up is the most common and most dangerous dosing error; use the mcg/mg toggle deliberately.
- The figures returned describe the arithmetic of the inputs you enter; they are not a recommended dose, frequency, or supply for anyone.
- A reconstituted vial does not last indefinitely even if doses remain — follow storage and beyond-use guidance for the specific product rather than using a vial until it is empty.
- Many research peptides are not approved for human use; the tool computes math only and is not a recommendation to obtain, prepare, or use any peptide.
This calculator is for educational purposes only and is not medical advice, diagnosis, or treatment. Results are estimates based on published formulas and population averages — your individual values may differ. Nothing here is calculated on a server: everything runs in your browser and no data is stored or sent anywhere. Always consult a qualified clinician before making health, medication, or training decisions.