Free calculator
Peptide reconstitution calculator
Reconstitution is just mixing: powder plus water. Type three numbers from your vial and your syringe. We tell you where to fill the syringe to, how many draws the vial holds, and show the math behind it.
Your numbers
Look at the label. It says a number in mg (milligrams). Tap a common size or type your own.
In mL (milliliters). Use the amount you actually put in. We do not suggest an amount; your label or doctor does.
The amount of peptide you want to pull into the syringe. Pick mcg or mg. This is your number, not ours.
1 mg = 1,000 mcg. Some labels write mcg as µg. Same thing.
Printed on the syringe. Most insulin syringes are "U-100": 100 units equals 1 mL.
This calculator only does math on the numbers you type. It does not tell you how much to use, how often, or how much water to add. Those are questions for a licensed doctor. Why we draw that line.
Your answer
Show me the math
The card shows your numbers so you can print it or keep it on your phone while you mix.
The rule we use: 100 units = 1 mL on a U-100 syringe (ISO 8537).
How the math works, in plain words
Step 1. Peptide in the vial, divided by water you added, is the strength of your liquid. Example: 5 mg in 2 mL of water is 2.5 mg in every mL.
Step 2. The amount you want, divided by that strength, is how much liquid to draw. Example: you want 0.25 mg. 0.25 divided by 2.5 is 0.1 mL.
Step 3. Liquid in mL, times 100, is the mark on a U-100 syringe. 0.1 mL is the 10 mark.
Step 4. Peptide in the vial, divided by the amount per draw, is how many draws you get. 5 divided by 0.25 is 20 draws.
Three examples you can check
These are also the tests we run on the calculator before every update. If any one fails, the update does not go live.
250 mcg is 0.25 mg. 5 / 2 = 2.5 mg/mL. 0.25 / 2.5 = 0.1 mL. 0.1 x 100 = 10 units. 5 / 0.25 = 20 draws.
Fill the syringe to the 10 mark. The vial holds 20 draws.
10 / 1 = 10 mg/mL. 1 / 10 = 0.1 mL. 0.1 x 100 = 10 units. 10 / 1 = 10 draws.
Fill the syringe to the 10 mark. The vial holds 10 draws.
100 mcg is 0.1 mg. 2 / 1 = 2 mg/mL. 0.1 / 2 = 0.05 mL. 0.05 x 100 = 5 units. 2 / 0.1 = 20 draws.
Fill the syringe to the 5 mark. The vial holds 20 draws.
Syringe marks, at a glance
| Liquid | Mark on a U-100 syringe | Fits in |
|---|---|---|
| 0.05 mL | 5 units | any insulin syringe |
| 0.10 mL | 10 units | any insulin syringe |
| 0.30 mL | 30 units | 0.3, 0.5 or 1 mL syringe |
| 0.50 mL | 50 units | 0.5 or 1 mL syringe |
| 1.00 mL | 100 units | 1 mL syringe |
Common questions
What does mg/mL mean?
How much peptide is in each milliliter of your liquid. It is the vial amount divided by the water you added. A 5 mg vial with 2 mL of water is 2.5 mg/mL.
What is a "unit" on the syringe?
A tiny slice of a milliliter. On a U-100 insulin syringe, 100 units is 1 mL, so each unit is 0.01 mL. Multiply your mL by 100 to get the mark.
How many draws are in my vial?
The vial amount divided by the amount you take each time. A 5 mg vial at 0.25 mg per draw gives 20 draws.
Does this tell me how much to use?
No. You type the amount. We only convert it into a syringe mark. We never suggest an amount, a schedule, or how much water to add. Here is why.
It says the draw does not fit my syringe. What now?
The mark you need is past the end of that syringe. A 0.3 mL syringe stops at 30 units. You would need a bigger syringe, or a different mix, and the mix is set by how much water you chose.
Is what I type saved anywhere?
The math runs on your own device, and nothing is sent as you type. If you tap "Save a card of this mix", we record the numbers and the peptide name you typed, anonymously, so we can see which mixes people need. Nothing else is saved, and nothing identifies you. The privacy page has the full list.
Still fuzzy on mg, mL and units?
Read how mixing works