Peptide reconstitution calculator
Enter the vial's milligrams, the bacteriostatic water to add and the target dose per draw. The tool computes concentration, volume per dose and the units in an insulin U-100 syringe.
Calculation tool for laboratory planning (RUO). An insulin U-100 syringe has 100 units = 1 ml. Laboratory reference, not medical advice.
Step by step, with your numbers
Your numbers
10 mg vial · 2 ml of water · 0.5 mg dose · 1 ml syringe
Complete the calculator above — the guide keeps your last valid calculation.
Step 1 of 4 Get what you need
Your vial, a vial of bacteriostatic water (sold separately), a 1 ml U-100 insulin syringe — ask for it exactly like that at the pharmacy — and alcohol wipes.
Step 2 of 4 Measure the water
The 10 mg vial takes 2 ml of water: 2 full draws to 100. Flip off the plastic cap (the rubber stopper stays on), wipe it with alcohol and let the water run down the inside wall.
Step 3 of 4 Swirl gently, never shake
Swirl the vial slowly until it turns clear — never shake it; some take a few minutes. Then it goes in the fridge (2–8 °C), away from light, and is used within 12 weeks — the limit is mainly to keep bacteria out each time the stopper is pierced.
Step 4 of 4 Fill to the 10 mark
The numbers printed on the syringe are units (U): 100 U = 1 ml. Your dose of 0.5 mg is 0.1 ml — draw up to the 10 mark.
Summary Done — you have the essentials
Your 10 mg vial yields 20 complete doses of 0.5 mg.
Order or ask on WhatsApp (opens WhatsApp in a new tab)Start from a vial in the catalog
Each button loads that presentation's real milligrams and a common water volume. You can adjust them afterwards.
Concentration of our vials
What concentration you get depending on the water you add, for every presentation in the catalog.
| Vial | 0.5 ml | 1 ml | 2 ml | 3 ml |
|---|---|---|---|---|
| Retatrutide · 5 mg | 10 mg/ml | 5 mg/ml | 2.5 mg/ml | 1.67 mg/ml |
| Retatrutide · 15 mg | 30 mg/ml | 15 mg/ml | 7.5 mg/ml | 5 mg/ml |
| Retatrutide · 30 mg | 60 mg/ml | 30 mg/ml | 15 mg/ml | 10 mg/ml |
| Tirzepatide · 20 mg | 40 mg/ml | 20 mg/ml | 10 mg/ml | 6.67 mg/ml |
| Tesamorelin · 10 mg | 20 mg/ml | 10 mg/ml | 5 mg/ml | 3.33 mg/ml |
| MOTS-c · 40 mg | 80 mg/ml | 40 mg/ml | 20 mg/ml | 13.33 mg/ml |
| BPC-157 + TB-500 · 10 mg | 20 mg/ml | 10 mg/ml | 5 mg/ml | 3.33 mg/ml |
| Ipamorelin + CJC-1295 · 10 mg | 20 mg/ml | 10 mg/ml | 5 mg/ml | 3.33 mg/ml |
| GHK-Cu · 50 mg | 100 mg/ml | 50 mg/ml | 25 mg/ml | 16.67 mg/ml |
| NAD+ · 500 mg | 1,000 mg/ml | 500 mg/ml | 250 mg/ml | 166.67 mg/ml |
| SEMAX · 10 mg | 20 mg/ml | 10 mg/ml | 5 mg/ml | 3.33 mg/ml |
| PT-141 · 10 mg | 20 mg/ml | 10 mg/ml | 5 mg/ml | 3.33 mg/ml |
U-100 syringe equivalence
How many units to draw depending on the concentration you prepared and the mass you want.
| Concentration | 0.1 mg | 0.25 mg | 0.5 mg | 1 mg | 2 mg |
|---|---|---|---|---|---|
| 1 mg/ml | 10 U | 25 U | 50 U | 100 U | 200 U |
| 2 mg/ml | 5 U | 12.5 U | 25 U | 50 U | 100 U |
| 2.5 mg/ml | 4 U | 10 U | 20 U | 40 U | 80 U |
| 5 mg/ml | 2 U | 5 U | 10 U | 20 U | 40 U |
| 10 mg/ml | 1 U | 2.5 U | 5 U | 10 U | 20 U |
| 20 mg/ml | 0.5 U | 1.3 U | 2.5 U | 5 U | 10 U |
Milligrams and micrograms
There is a factor of a thousand between a milligram and a microgram. It is the most common mistake when reconstituting, and the most expensive: getting the unit wrong does not shift the result slightly, it multiplies or divides it by a thousand.
Vials are labelled in milligrams and much of the research literature speaks in micrograms. A 10 mg vial holds 10,000 mcg. If a protocol says 250 mcg, that is 0.25 mg — one fortieth of the vial, not a quarter. The calculator asks for the dose in milligrams and shows the microgram equivalent underneath, so you never have to do that conversion in your head.
Reading an insulin syringe
A U-100 syringe has 100 units per millilitre, so each unit is 0.01 ml. To convert: divide the mass you want by the concentration in mg/ml and multiply by 100.
What changes between syringes is barrel capacity, and with it precision — and the value of each line: on 0.3 and 0.5 ml syringes it is usually 1 unit (some 0.3 ml ones mark half units), on a 1 ml syringe usually 2 units, so go by the printed numbers, not by counting lines. 40 units fit comfortably in a 1 ml syringe and do not fit at all in a 0.3 ml one — that is why the selector above matters. The tool warns you when the volume does not fit the barrel you picked.
Frequently asked questions
How many units is 0.5 mg?
It depends on the concentration you prepared, not on the peptide. At 2.5 mg/ml it is 20 units; at 5 mg/ml, 10; at 10 mg/ml, 5. The formula: mass in mg ÷ concentration in mg/ml × 100.
Does it work for non U-100 syringes?
The calculator assumes U-100, the standard for human insulin syringes. A veterinary U-40 syringe holds 40 units per millilitre instead of 100, so the units are not equivalent. Check what is printed on the barrel.