Pindrop

GLP-1 Dose Calculator

For compounded GLP-1 vials that arrive as a powder. Enter the vial strength, the water you added, and your dose in milligrams to get the units to draw.

mg

Total mg in the vial.

mL
mg

e.g. 0.25, 1.0, 2.5

Syringe

Draw on the syringe

25units

0.25 mL at 10 mg/mL
0102030405060708090100
Concentration
10mg/mL
Doses per vial
4
Volume
0.25mL

What this calculator does

Compounded semaglutide and tirzepatide often ship as a freeze-dried powder that you mix yourself, which means the units on the syringe depend entirely on how much water you add. This calculator handles that conversion. It takes the milligrams of drug in the vial, the water you reconstitute with, and your dose in milligrams, then returns the exact units to pull on a U-100 insulin syringe.

GLP-1 doses are small and step up over weeks, so the difference between one tick and two is the difference between the plan and a mistake. Enter your dose the way the protocol writes it, in milligrams like 0.25 or 2.5, and the calculator does the microgram conversion for you.

Reading the result

The main number is where to stop on the plunger. Below it you get the solution strength in mg/mL, the volume in milliliters, and how many doses the vial holds so you can plan reorders. If your dose is larger than the vial contains, or the draw overflows the syringe you chose, a warning says so. This is a math tool; titration schedules and target doses come from your provider.

Common questions

How much bacteriostatic water do I add to compounded semaglutide or tirzepatide?
Use the volume your provider or the vial instructions specify — the water sets the concentration, and your dose depends on it. 1 to 2 mL is common. Enter the vial strength and your water volume to see the units for your dose.
How do I convert a GLP-1 dose in mg to syringe units?
Divide your dose by the solution concentration to get the volume, then read it on a U-100 syringe where 1 mL is 100 units. This calculator does it: enter the vial strength in mg, the water in mL, and your dose in mg.
Why are GLP-1 doses so small on the syringe?
Semaglutide and tirzepatide are dosed in small milligram amounts that step up over weeks, so the volume is tiny, often well under 20 units. That is why the concentration and the draw matter: a single tick is a meaningful fraction of the dose.
My dose is in clicks or a pen chart. Can I use this?
This calculator is for a reconstituted vial and an insulin syringe, not a pen dial. If you use a multi-dose pen, follow the pen dosing. If you draw from a vial with a syringe, this is the tool.
What syringe should I use for GLP-1 doses?
A U-100 insulin syringe. A 0.3 mL (30-unit) or 0.5 mL (50-unit) barrel is easiest to read for the small volumes GLP-1 doses usually need.

Pindrop is a calculation tool, not medical advice. Confirm your dose and protocol with a licensed healthcare provider.