# Peptide Dosage Calculator

Calculate peptide reconstitution and injection dosing. Enter vial amount, water volume, and desired dose to find the exact injection volume in mL and insulin syringe units.

## What this calculates

Getting the right dose from a reconstituted peptide vial requires a simple concentration calculation. Enter your vial size, the amount of bacteriostatic water you added, and your desired dose to find exactly how much to draw per injection.

## Inputs

- **Peptide in Vial** (mg) — min 0.1, max 100 — Total peptide amount in the vial (in milligrams)
- **Bacteriostatic Water Added** (mL) — min 0.1, max 20 — Volume of bacteriostatic water used to reconstitute
- **Desired Dose** (mcg) — min 1, max 50000 — Desired dose per administration in micrograms
- **Doses per Day** — options: Once daily, Twice daily, Three times daily

## Outputs

- **Reconstituted Concentration** — formatted as text — Concentration of the reconstituted peptide solution
- **Volume per Dose** — formatted as text — Volume to draw for each dose
- **Insulin Syringe Units** — formatted as text — Units on a standard U-100 insulin syringe (100 units = 1 mL)
- **Doses per Vial** — Total number of doses available from one vial
- **Vial Duration** — formatted as text — How long one vial lasts at your dosing frequency

## Details

Peptide reconstitution math is simple once you understand the relationship between the vial contents, water volume, and concentration.

The formula is: **Volume per dose (mL) = Desired dose (mcg) / Concentration (mcg/mL)**

And the concentration is: **Concentration (mcg/mL) = Total peptide (mcg) / Water added (mL)**

For example, if you have a 5 mg vial (5,000 mcg) and add 2 mL of bacteriostatic water, the concentration is 2,500 mcg/mL. To get a 250 mcg dose, you need 250 / 2,500 = 0.1 mL, which is 10 units on a U-100 insulin syringe.

Most researchers use U-100 insulin syringes where 100 units = 1 mL. The small graduations make it easy to measure precise volumes. A 0.1 mL dose equals 10 units, 0.05 mL equals 5 units, and so on.

The amount of bacteriostatic water you add is flexible. More water means a lower concentration and larger injection volumes (easier to measure precisely). Less water means higher concentration and smaller volumes (less injection discomfort). Common reconstitution volumes are 1 mL, 2 mL, or 3 mL per vial.

**Disclaimer:** This calculator is for research and educational purposes only. It does not constitute medical advice. Consult a licensed healthcare provider before using any peptide or injectable substance.

## Frequently Asked Questions

**Q: How much bacteriostatic water should I add?**

A: The amount of water is flexible and depends on your preferred injection volume. Adding 2 mL to a 5 mg vial gives a concentration of 2,500 mcg/mL, which is a good balance between precision and injection volume. Adding 1 mL gives a more concentrated solution (5,000 mcg/mL) with smaller injection volumes. Adding 3 mL gives a more dilute solution (1,667 mcg/mL) that is easier to measure small doses precisely. Choose whatever makes your target dose convenient to measure on your syringe.

**Q: How do I read insulin syringe units?**

A: A standard U-100 insulin syringe has 100 units per 1 mL. Each small tick mark typically represents 1 or 2 units depending on the syringe size. For a 1 mL (100 unit) syringe, the 50-unit line is the halfway point (0.5 mL). For a 0.5 mL (50 unit) syringe, each tick is usually 1 unit. To convert mL to units, multiply by 100. So 0.1 mL = 10 units, 0.25 mL = 25 units.

**Q: How long does a reconstituted vial last?**

A: Reconstituted peptides mixed with bacteriostatic water typically remain stable for 28-30 days when refrigerated at 2-8 degrees C (36-46 degrees F). The bacteriostatic water contains 0.9% benzyl alcohol as a preservative, which prevents bacterial growth. Never freeze reconstituted peptides, and always store them upright in the refrigerator. Peptides mixed with sterile water (without preservative) should be used within a few days.

**Q: What is the difference between mg and mcg?**

A: One milligram (mg) equals 1,000 micrograms (mcg). Peptide vials are typically labeled in milligrams (e.g., 5 mg, 10 mg), while doses are often prescribed in micrograms (e.g., 100 mcg, 250 mcg, 500 mcg). To convert: 5 mg = 5,000 mcg. This calculator handles the conversion automatically when you enter the vial amount in mg and the dose in mcg.

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Source: https://vastcalc.com/calculators/health/peptide-dosage
Category: Health & Fitness
Last updated: 2026-04-08