Peptide Vial Calc · free, no signup
Peptide calculator
Turn your entered mg or mcg into mL and U-100 syringe units. Start with your vial below.
Your syringe draw
U-100 · 1 mLYour syringe draw will appear here.
Enter your vial amount, water added, and dose or number of injections.
Calculated syringe draw
Vial totals & calculation details
Calculated from a full vial, before liquid left in the vial or syringe.
Show the math
Calculates the amounts you enter. It doesn’t select a dose or check the product. How the math works
Check a result before relying on it
This peptide vial calculator connects three different quantities: the peptide amount in mg or mcg, the liquid volume in mL, and the marks on a confirmed U-100 syringe. A vial’s mg label alone cannot tell you how many units to draw.
- Two calculators disagree? Compare their concentrations side by side.
- Check your syringe’s capacity and line spacing, or save the U-100 reference card.
- Work backward from a chosen draw, or split your full vial into equal amounts.
Calculations stay in your browser. See the synthetic verification examples, sources and calculation limits.
How to calculate peptide syringe units
- Enter your target dose. Use the amount you want to calculate for one injection, and check mg or mcg.
- Enter your vial details. Use the amount in the full vial and the total water you added. If your label gives mg/mL, choose that option instead.
- Read “Draw this amount.” The result gives U-100 syringe units and the matching mL. Check the syringe settings and any measurement note.
mg is peptide mass; mL is liquid volume. On U-100, 100 syringe units equals 1 mL. Water-added results estimate the finished volume.
U-100 units = target dose (mg) ÷ concentration (mg/mL) × 100.
See the peptide calculation formulas →How many syringe units are in 1 mg?
There is no fixed mg-to-units conversion without the concentration. For a hypothetical solution labeled 5 mg/mL, 1 mg corresponds to 0.2 mL, or 20 U-100 units. At 10 mg/mL, the same 1 mg corresponds to 0.1 mL, or 10 units. These examples illustrate the formula; they are not target doses.
Can I enter how many injections I want?
Yes. Open “Split the vial equally” and enter a whole number. The calculator divides the full vial by that number and shows the amount and liquid volume per injection. This is arithmetic, not a recommended dose or schedule.
Do I enter the water I added?
Yes. Enter the total bacteriostatic water you added when mixing the vial. The calculator uses that amount as the estimated mixed volume and labels the result as an estimate. The final volume may differ. If your label gives a concentration in mg/mL, use that directly.
My vial is still powder. Where do I start?
Choose “Mix a new vial.” Enter your target dose or injection count, the amount in your vial, and your syringe line spacing. Compare water amounts and their estimated draws, then select an option or enter your own water amount. “Easy to measure” highlights a measurement preference; follow your product’s directions for the appropriate liquid and amount.
Why does the calculator ask about the syringe lines?
Two 1 mL syringes can have different line spacing. Your calculated draw still appears if it falls between printed lines, with a note explaining the mismatch. We don’t round it to a different dose. Draws exceeding the selected syringe’s capacity remain errors.
Does this work with peptide blends?
Use a single-ingredient vial. Adding different peptide amounts together does not give the dose of each ingredient, so blends are outside this calculator’s scope.