Peptide Dosage Calculator

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Peptide therapy is growing rapidly in research and clinical settings, but one of the trickiest parts of working with peptides is getting the reconstitution and dosing math right. A lyophilised (freeze-dried) peptide vial needs to be mixed with the correct volume of bacteriostatic water, and then each injection needs to draw the right amount based on the desired microgram dose. One arithmetic mistake can mean a dose that is ten times too high or too low. The Peptide Dosage Calculator eliminates that risk by handling every step of the calculation for you.

How Peptide Reconstitution Works

Peptides are typically sold as a dry powder in vials containing a specific total amount -- commonly measured in milligrams (mg). Before use, the powder must be dissolved in a sterile solvent, usually bacteriostatic water (BAC water). The amount of water you add determines the concentration of the resulting solution, which in turn determines how much liquid you draw for each dose.

For example, a vial containing 5 mg of peptide reconstituted with 2 mL of BAC water creates a solution where each 0.1 mL (10 units on a standard insulin syringe) contains 250 mcg. Our calculator does this arithmetic for any combination of vial size, water volume, and desired dose, giving you the exact number of units to draw per injection.

Step-by-Step Calculator Usage

Step 1: Enter the total amount of peptide in your vial (in milligrams). This is printed on the vial label.

Step 2: Enter the volume of bacteriostatic water you plan to add (in millilitres). Common volumes are 1 mL, 2 mL, or 5 mL depending on the peptide and your preferred concentration.

Step 3: Enter your desired dose per injection (in micrograms). Your prescribing clinician or research protocol specifies this.

The calculator then displays: the concentration of your reconstituted solution (mcg per unit), the volume to inject per dose (in mL and in syringe units), the total number of doses per vial, and how many days the vial will last at your dosing frequency.

Why This Math Matters So Much

Peptide dosing operates in micrograms, which are one-thousandth of a milligram. The difference between 100 mcg and 1000 mcg is a simple decimal place error, but the physiological consequences are enormous. Under-dosing wastes expensive peptides and produces no therapeutic effect. Over-dosing can cause side effects ranging from mild (headaches, flushing, nausea) to severe. Using a dedicated calculator removes the mental arithmetic that leads to these errors.

Common Peptides and Typical Dosing Ranges

While specific dosing should always follow professional guidance, being familiar with typical ranges helps you verify your calculations. Research peptides like BPC-157 are often studied at 250 to 500 mcg per dose. Others have much lower effective ranges, measured in single-digit micrograms. The calculator works for any peptide and any dose -- just enter the numbers from your protocol.

Syringe Reading Tips

Insulin syringes are marked in "units" where 100 units equals 1 mL. Each small tick on a standard U-100 syringe represents 1 unit (0.01 mL). When the calculator tells you to draw 20 units, you fill to the 20 mark on the syringe. If the calculated volume falls between tick marks, the calculator rounds to the nearest unit and shows the resulting actual dose so you know exactly what you are getting.

Storage and Vial Longevity

Once reconstituted, most peptides should be stored in a refrigerator (2 to 8 degrees Celsius) and used within a specific timeframe, typically 14 to 30 days depending on the peptide. The calculator shows how many doses your vial contains, which helps you plan whether you will use it within its shelf life or whether a smaller reconstitution volume would be more appropriate.

Accurate, Fast, and Private

This peptide dosage calculator runs entirely in your browser. No health data is stored or transmitted. Enter your numbers, get your results, and proceed with confidence that your reconstitution and dosing calculations are correct down to the last unit.