Dose Calculator
Three questions and you have your number. You do not need to know what a concentration is, and you do not need to do any math — just read what is printed on your vial and copy it in.
1 Pick up your vial. Which one looks like yours?
Read the label. One of these three will match it.
If your label matches none of these, do not guess and do not inject. Photograph the label and send it to your clinician.
2 Copy the numbers off the label
The number before the slash.
Fill this in and we will also tell you how long the vial lasts.
The bigger number.
The number followed by mL.
The only number on the vial.
Use the amount your clinician gave you. Do not pick a number yourself — it changes every figure below.
3 How much are you taking?
The dose your clinician prescribed, in the units they wrote it in.
Tells you how many doses are in the vial and how long it lasts.
4 Your answer
What is a U-100 syringe, and why units?
A U-100 insulin syringe is marked so that 100 units is exactly 1 milliliter of liquid. One unit is 0.01 mL. It is the standard syringe for a subcutaneous injection, and it is what every number on this page refers to.
The marks measure liquid, not medication. That is the part people get wrong. Two people can both draw to 20 units and be taking wildly different doses, because what matters is how much drug was dissolved in that liquid. This is also why one full syringe — 100 units — is a hard stop: past that you are no longer giving a subcutaneous injection, whatever the label says.
Why does mixing a powder change my number?
A dry vial has a fixed amount of drug in it and no liquid at all. The liquid you add is what creates the strength.
Put 5 mL of bacteriostatic water into a 15 mg vial and every milliliter holds 3 mg. Put 2 mL into the same vial and every milliliter holds 7.5 mg — two and a half times as concentrated, from the same box. A 1 mg dose is 33 units in the first case and 13 units in the second.
Same vial, same dose, completely different mark on the syringe. Use the volume your clinician specified.
This calculator converts a prescribed dose into a volume. It does not decide what your dose should be, and it is not medical advice. BioForge treats patients in Florida only — the calculator is free for anyone to use.
My vial is a powder. What strength do I enter?
None — a powder has no strength until you mix it. That is why this calculator asks for the milligrams in the vial and the amount of liquid you add, and works the strength out for you. Adding 5 mL to a 15 mg vial gives you 3 mg per mL. Adding 2 mL to the same vial gives you 7.5 mg per mL and a completely different number on your syringe.
How many units is a 0.5 mg dose?
There is no single answer, and that is the point. Units measure liquid, not medication. 0.5 mg drawn from a 3 mg/mL vial is 17 units. The same 0.5 mg from an 8 mg/mL vial is 6 units. The strength has to be part of the calculation every time.
What is a U-100 syringe?
An insulin syringe marked so that 100 units is exactly 1 milliliter of liquid. One unit is 0.01 mL. The marks measure how much liquid you pull in, not how much drug is in it — which is why two people drawing to the same mark can be taking very different doses.
How much bacteriostatic water should I add?
Use the amount your clinician tells you, or the amount printed on the vial. Do not pick a number yourself. The volume you add sets the strength, and the strength sets every unit figure that follows.
My new box says something different from my last one. What do I do?
Run the numbers again using the box in your hand. Never reuse a unit figure from a previous vial. Pharmacies ship different strengths, and the same prescribed dose lands on a different mark.
My dose comes out above 100 units. What now?
Stop. Above 100 units is more than one full syringe and it is not a subcutaneous dose. Do not split it across two syringes. It almost always means the vial strength is wrong for the dose. Call your clinician before you inject.
My dose comes out under 10 units. Is that a problem?
It can be. A U-100 syringe is marked in whole units, so at a 5-unit draw being one mark off is a 20 percent dosing error. At 25 units the same slip is 4 percent. When a dose lands that low the fix is a weaker vial, not a steadier hand — ask your clinician for one.
How long will my vial last?
Divide the liquid in the vial by the liquid in one dose. This page does it for you once you enter how often you inject. Then check that number against the beyond-use date printed on your label, because a reconstituted peptide has a shelf life once it is mixed — a vial holding ninety days of doses is not a ninety-day supply if it expires at twenty-eight.
Want a protocol built from your own bloodwork?
Every BioForge protocol starts with labs and a clinician. The first 15-to-30-minute call is free and nothing is ordered before it.