← Full peptide calculator
Free tool
Enter your vial size, dose, injection frequency, and how many vials you have to see how long your supply lasts and when to reorder. Because a reconstituted vial should be discarded at its 28-day beyond-use date, the planner caps each open vial at that window and flags when you’d waste peptide. Reference math, not medical advice.
At this dose and frequency a vial holds ~20 doses (20 weeks), but a reconstituted vial should be discarded after the 28-day beyond-use date — so you'd use only ~4 doses before it expires. A smaller vial or fewer weeks between mixes reduces waste.
Doses per vial = vial mg ÷ dose. Weeks of supply assumes each opened vial is used within the 28-day USP <797> beyond-use window; longer than that is capped and flagged. Reorder-by leaves about a week of buffer. Arithmetic and reference only — not medical advice; follow your product label and a clinician.
Frequently asked questions
How long will one peptide vial last?
Divide the vial strength by your dose to get doses per vial, then divide by your injections per week to get weeks per vial. A 10 mg vial dosed at 0.5 mg once a week is 20 doses, or 20 weeks by the numbers — but see the beyond-use limit below.
Why does the planner cap a vial at 28 days?
A reconstituted multi-dose vial has a beyond-use date, commonly 28 days refrigerated under USP Chapter 797. Once opened it should be discarded at that point even if solution remains, so the usable time per vial is capped at four weeks regardless of how many doses are left.
Why does it say I’m wasting peptide?
If a vial holds more doses than you can use within 28 days, the extra doses expire before you reach them. Using a smaller vial, mixing less at a time, or a higher labeled dose reduces that waste. The tool shows how many doses you would actually use before the beyond-use date.
When should I reorder?
The reorder-by date leaves about a week of buffer before your supply runs out, so a new vial arrives before you need it. Adjust for your own supplier’s shipping time. The date updates as you change your dose, frequency, or vials on hand.
Is this medical advice?
No. It is arithmetic and reference only. It does not recommend a dose, a frequency, or a product, and the beyond-use date is a general benchmark, not product-specific. Verify storage and dosing with the product label and a clinician.