How Long Will a Vial Last?
You can stop counting days on a wall calendar with a few dates circled. This how long will a vial last calculator uses what is left, your amount per draw, and the days between draws. You see full draws, a run out date, and any amount left after the last full draw.
Calculator
Enter your numbers to see the answer.
The math
Example entries
Example entries: 10 mg left, 0.5 mg per draw, every other day, counting from Oct 12, 2026. Result: 20 full draws, last Thu, Nov 19, 2026. This is an example for the arithmetic, not an amount to take.
Formulas: full draws = mg left / amount per draw, rounded down. The last draw date is the date of that draw on the schedule you enter.
- Doses left = 10000 mcg / 500 mcg = 20 full doses (0 mcg over).
- Schedule: every other day, first day 2026-10-12.
- Dose 20 falls on 2026-11-19, so the vial is empty from 2026-11-20.
Math based on your entries. Check it against the print on your syringe. Not medical advice.
The math
Start with what is left in the vial. Divide the remaining amount by the amount per draw, and you get the number of full draws.
The next part is the timeline. Multiply the number of full draws by the days between draws, and you get the last day for those full draws.
You can also see what remains after that. The calculator shows the leftover amount after the final full draw, so you can check the arithmetic line by line.
If you came here from a reconstitution calculator, bring over the same numbers from that result. If a number looks off, the example below makes the layout easier to follow.
The result is arithmetic, not a rule. Your plan decides the amount per draw and the spacing between days.
Check the expiry date on your label
The date on your label still wins over the run out date shown here. Use the calculator's date as a count based on your entries, then compare it with the label or with what your pharmacist or prescriber gave you.
If you need where to find your expiry date, that page can help you locate it. For anything beyond the arithmetic, follow the label and ask your pharmacist or prescriber.
Keep it up to date automatically
If you want this vial in one place, save it in the peptide tracker or the GLP-1 tracker. You can also Save as a vial from the tool. If it fits your setup, use Get an alert 5 days before so the date stays visible.
Read this first. Math based on your entries. This page does arithmetic on the numbers you type. It does not recommend an amount, a schedule or a product. Check every result against your label and talk to your prescriber or pharmacist. 18+.
Editorial review against cited sources. Last checked Oct 12, 2026.