Calculate peptide reconstitution and injection doses. Converts vial content, bacteriostatic water volume, and syringe units for BPC-157, TB-500, Ipamorelin, CJC-1295, and more.
The Peptide Dosage Calculator simplifies the reconstitution and dosing of research peptides by converting between vial content (mg), bacteriostatic water volume (mL), desired dose (mcg), and insulin syringe units. Peptide reconstitution math is one of the most common sources of confusion and error when working with lyophilized peptides, because it requires converting between milligrams, micrograms, milliliters, and syringe units — four different measurement systems that must align perfectly.
Most peptides arrive as a freeze-dried (lyophilized) powder in a vial labeled in milligrams (e.g., 5 mg). The user adds bacteriostatic water to reconstitute the powder into a liquid solution. The concentration of this solution depends on how much water is added — and this directly determines how many units to draw on an insulin syringe for each dose. Getting this calculation wrong means taking too much or too little peptide, which can affect both safety and results.
This calculator handles the entire reconstitution chain: enter the vial content, how much bacteriostatic water you added, your desired dose in micrograms, and the syringe size — and it instantly shows the exact number of units to draw on the syringe. It also calculates how many doses each vial provides, daily totals, days of supply, and includes a reference table with typical dosing protocols for popular research peptides.
Reconstitution math errors are the most common mistake when working with peptides. A miscalculation between mg and mcg, or confusion about syringe unit markings, can result in taking 10× too much or too little. This calculator eliminates the math and provides clear unit markings for safe, accurate dosing. Keep these notes focused on your operational context. Tie the context to the calculator’s intended domain.
Concentration (mcg/mL) = Vial Content (mg) × 1000 ÷ BAC Water (mL) Volume per Dose (mL) = Desired Dose (mcg) ÷ Concentration (mcg/mL) Syringe Units = Volume (mL) × Syringe Size (units/mL) Doses per Vial = Vial Content (mcg) ÷ Dose (mcg) Days Supply = Doses per Vial ÷ Injections per Day
Result: Draw to 5.0 units (0.050 mL) = 250 mcg BPC-157; 20 doses per vial
A 5 mg vial reconstituted with 2 mL BAC water creates a concentration of 2500 mcg/mL. For 250 mcg: 250 ÷ 2500 = 0.05 mL = 5.0 units on a 100-unit insulin syringe. The vial contains 5000 mcg total, which provides 20 doses of 250 mcg.
To reconstitute a lyophilized peptide: (1) Allow the vial and bacteriostatic water to reach room temperature. (2) Clean both vial stoppers with an alcohol swab. (3) Draw the desired volume of BAC water into a syringe. (4) Insert the needle through the peptide vial stopper and slowly inject the water against the inner glass wall — not directly onto the powder cake. (5) Gently swirl the vial in circular motions until the powder is fully dissolved. This typically takes 30–120 seconds. The solution should be clear and colorless. (6) Label the vial with the date, peptide name, and concentration.
Insulin syringes are the standard for peptide injection because they provide the fine gradations needed for accurate small-volume dosing. A U-100 insulin syringe (100 units = 1 mL) is the most common. For very small doses, a 30-unit syringe (0.3 mL) with half-unit markings provides the best precision. When measuring, hold the syringe at eye level and read from the flat bottom of the meniscus. Even a 2-unit error on a 100-unit syringe can represent a significant percentage change in dose for concentrated solutions.
Lyophilized peptides are remarkably stable and can be stored frozen (−20°C) for months to years without significant degradation. Once reconstituted, the peptide solution must be refrigerated (2–8°C) and is typically stable for 28–30 days. Bacteriostatic water's benzyl alcohol preservative inhibits bacterial growth but does not prevent all contamination — always use aseptic technique when drawing from the vial. Reconstituted peptides should never be frozen, as ice crystal formation can denature the peptide. Discard any solution that becomes cloudy, discolored, or contains particulate matter.
Common choices are 1–5 mL. Less water creates a more concentrated solution (fewer units per dose, but harder to measure small doses accurately). More water gives a more dilute solution that is easier to measure precisely. For most peptides, 2 mL is the standard recommendation.
Bacteriostatic water (BAC water) is sterile water with 0.9% benzyl alcohol as a preservative. The preservative allows the reconstituted peptide solution to remain usable for multiple injections over days or weeks. Regular sterile water should only be used for single-dose vials.
A standard insulin syringe has 100 units per mL. So 10 units = 0.1 mL, 5 units = 0.05 mL, 1 unit = 0.01 mL. A 50-unit syringe holds 0.5 mL total, and a 30-unit syringe holds 0.3 mL total.
Reconstituted peptides stored in bacteriostatic water are generally stable for 28–30 days when refrigerated (2–8°C). Lyophilized (unreconstituted) peptides can last months to years when frozen. Never freeze reconstituted peptide solutions.
Research protocols typically use 200–500 mcg of BPC-157 once or twice daily, injected subcutaneously near the area of injury. A 5 mg vial at 250 mcg/dose provides 20 injections. Oral capsule forms also exist but have lower bioavailability.
Some peptides are commonly stacked (e.g., Ipamorelin + CJC-1295). They can be drawn into the same syringe if both are reconstituted separately first. However, do not mix peptides in the same vial, as they may interact and degrade.