Peptide Reconstitution & Dosage Calculator

It performs three divisions. First, it divides the peptide amount in the vial (mg) by the water volume you added (mL) to get the concentration in mg/mL. Second, it divides your target amount (mg) by that concentration to get the draw volume in mL. Third, it multiplies the draw volume by 100 to get U-100 syringe units, because 1 mL equals 100 units on a U-100 insulin syringe. The tool only does this arithmetic; it never suggests what target amount to enter.

100 units. The U-100 scale is defined as 100 units per 1 mL, so 1 unit equals 0.01 mL. To convert any volume in mL to U-100 units, multiply by 100; to convert units back to mL, divide by 100. This conversion is a property of the syringe scale, not of any particular substance.

Multiply milligrams by 1000 to get micrograms, or divide micrograms by 1000 to get milligrams. For example, 0.5 mg equals 500 mcg. Keeping both numbers in the same unit before dividing is the most common way to avoid 1000-fold errors in reconstitution math.

Divide the total peptide in the vial (mg) by the target amount per draw (mg). For example, a 10 mg vial with a 0.5 mg target per draw holds 20 draws. The calculator shows this as doses per vial. It is a count of how many equal portions fit in the vial, not a schedule or recommendation.

Because the same amount of peptide is spread through more liquid, so the concentration falls. Concentration equals vial mg divided by water mL, so doubling the water halves the concentration, and a fixed target amount then needs twice the volume and twice the units to deliver. The tool recalculates this automatically when you change the water volume.

Most insulin syringes are marked in 1-unit graduations (some have half-unit marks), so a fractional result such as 7.5 units cannot be read exactly on every syringe. The calculator flags fractional results and shows the volume in mL alongside, so you can see the exact value.

Bacteriostatic water is water for injection containing 0.9% benzyl alcohol as a preservative; sterile water for injection has no preservative. For the arithmetic, only the volume you added matters: the calculator uses your entered mL figure regardless of diluent type. Questions about which diluent, storage, or handling are appropriate belong to your pharmacist or clinician, not to a math tool.

No. It is educational math only. You enter the target amount yourself, and the tool converts it into mL and U-100 units. It does not suggest, verify, or endorse any target amount, and it must not be used without guidance from a qualified clinician.

A small draw volume means the concentration is high relative to your target amount. Since draw volume equals target amount divided by concentration, and concentration equals vial mg divided by water mL, adding more water lowers the concentration and increases the draw volume for the same target. That is a mathematical relationship; vial capacity and handling limits are separate practical questions for your clinician or pharmacist.

The calculator refuses the calculation and explains why: one vial cannot supply more peptide than it contains. Check that the vial amount, the water volume, and the target amount are entered in the right units (mg versus mcg mix-ups are the usual cause), then recalculate.

Work the three steps with your own numbers. Example: 5 mg vial plus 2 mL water gives 2.5 mg/mL. A 250 mcg (0.25 mg) target divided by 2.5 mg/mL gives 0.1 mL. Multiply by 100 to get 10 units. If your hand calculation matches the tool on two different inputs, the arithmetic is consistent.

The arithmetic itself, dividing an amount by a volume, is the same everywhere. But this tool is presented as general educational math and does not endorse any particular use. Dosing decisions for people belong to a qualified clinician; for animals, to a veterinarian; laboratory work follows its own protocols. The tool replaces none of them.

Divide the vial content by the target concentration. For example, a 5 mg vial at a target of 2.5 mg/mL needs 5 / 2.5 = 2 mL of diluent. The diluent solver section above performs this division and flags results that look unusually large or small. It is a volume calculation, not a recommendation about any target.

The number is the units per mL: a U-100 syringe holds 100 units per mL, while a U-40 syringe holds 40 units per mL. So 0.5 mL measures 50 units on a U-100 syringe but only 20 units on a U-40 syringe. Using the wrong scale is a classic unit error, so this page lets you pick the scale explicitly in the calculator and converter.

Displacement is the volume the dry powder itself occupies once dissolved, so the final liquid volume is the water you added plus the displacement. For example, 5 mg of powder in 2 mL of water with 0.2 mL displacement gives 2.2 mL final and 5 / 2.2 = 2.2727 mg/mL. The calculator accepts an optional displacement input; left at zero, it uses the water volume alone.