Peptide Dosage Calculator

Take the guesswork out of peptide reconstitution and dosing. Our calculator helps you convert between milligrams (mg) and International Units (IU) so you always know exactly how much you're drawing up.

How to Use the Calculator

Using the calculator is straightforward. Simply enter:

• The amount of peptide in your vial (mg) — found on the vial label

• The volume of bacteriostatic water used to reconstitute (mL) — the amount you added to the vial

• Your desired dose — in either mg or IU

The calculator will instantly show you the corresponding measurement in the other unit, along with the exact volume to draw into your syringe.

Understanding mg vs. IU

If you're new to peptides, the difference between milligrams and International Units can be confusing. Here's a simple breakdown:

• mg (milligrams) measures the actual mass of the peptide compound.

• IU (International Units) is a unit based on biological activity, commonly used with peptides like HGH and other growth factors.

Not all peptides use IU — many are dosed purely in mg or mcg (micrograms). Our calculator handles both, so you're covered regardless of how your peptide is measured.

Why Accurate Dosing Matters

Precision is important when working with peptides. Incorrect calculations can result in under-dosing (reducing effectiveness) or over-dosing (increasing the risk of unwanted effects). Using a reliable calculator removes the risk of manual math errors and helps ensure a consistent experience every time.

Reconstitution Basics

Before you can dose a peptide, it typically needs to be reconstituted — meaning a liquid (usually bacteriostatic water) is added to the lyophilized (freeze-dried) powder in the vial. The amount of water you use directly affects the concentration, which is why it's a required input in the calculator.

Example: If you have a 5mg vial and add 2mL of bacteriostatic water, your concentration is 2.5mg/mL. From there, the calculator determines exactly how many units to draw for your target dose.

How to Mix Your Peptide

Proper mixing technique protects the integrity of the peptide and ensures accurate dosing.

Step 1 — Prepare your workspace. Work on a clean, flat surface. Wash your hands thoroughly and gather everything you need before you begin: your peptide vial, bacteriostatic water, a fresh syringe, and alcohol swabs.

Step 2 — Swab both vial tops. Wipe the rubber stopper of both the peptide vial and the bacteriostatic water vial with an alcohol swab. Swipe in one direction only and allow the alcohol to fully air dry (about 15–30 seconds) before proceeding.

Step 3 — Draw air, then water. Pull back the syringe plunger to draw in air equal to your desired water volume. Insert the needle into the bacteriostatic water vial and inject the air in, then draw out the correct amount of water.

Step 4 — Add water slowly to the peptide vial. Insert the needle into the peptide vial and direct the water gently down the inside wall of the glass — not directly onto the powder. Inject slowly to avoid disturbing the peptide.

Step 5 — Swirl, never shake. Once the water has been added, gently roll the vial between your palms or swirl it slowly in a circular motion. Never shake the vial. Shaking introduces air bubbles and can degrade the peptide structure. Allow a few minutes if the powder is slow to dissolve.

Step 6 — Inspect before use. The solution should appear clear once fully dissolved. If it remains cloudy, contains floating particles, or has changed colour, do not use it.

Mixing at Room Temperature

Peptides should always be mixed at room temperature. If your vial has been in a particularly cold environment, allow it to sit at room temperature for 10–15 minutes before adding bacteriostatic water to ensure the powder dissolves fully and evenly.

Some Peptides Require Acetic Acid Solution

Most peptides reconstitute well with bacteriostatic water alone, but a small number do not dissolve properly in water and require acetic acid (AA) solution — typically 0.6% acetic acid — to reconstitute correctly. Using plain bacteriostatic water with these peptides can result in incomplete dissolution or a cloudy solution.

Peptides that typically require acetic acid solution include:

• AOD-9604 — a fragment of the HGH molecule; does not dissolve well in plain water

• Tesamorelin — a GHRH analogue; requires AA solution for proper reconstitution

• SLU-PP-332 — an ERR agonist; poorly water-soluble and requires AA solution

• CJC-1295 (without DAC) — some formulations benefit from AA solution, particularly at higher concentrations

• Ipamorelin — occasionally requires AA solution depending on the formulation and manufacturer

• GHRP-2 and GHRP-6 — most formulations reconstitute in BAC water, but AA solution may be needed if dissolution is incomplete

If your peptide does not fully dissolve after gently swirling in bacteriostatic water, AA solution is usually the next step. When using acetic acid solution, it is common practice to then dilute further with bacteriostatic water after the powder has dissolved, to bring the solution to a more comfortable injection concentration.

Note: Always check the specific reconstitution guidance for your peptide before mixing. When in doubt, contact your supplier for clarification.

How to Store Your Peptide

Correct storage is just as important as correct mixing. Improper storage can reduce potency or render a peptide completely inactive.

Before reconstitution (lyophilized powder): Unmixed peptide powder can be stored at room temperature, away from direct sunlight, heat sources, and humidity. A cupboard or drawer away from windows is ideal.

After reconstitution (mixed solution): Once mixed, peptides can continue to be stored at room temperature, again away from direct sunlight and heat. Keep the vial in a cool, dark place such as a drawer or cupboard. Always refer to the specific guidance for your product as stability windows vary by peptide.

Key storage rules:

• Store away from direct sunlight — UV exposure can degrade peptides over time

• Keep away from heat sources such as radiators, windowsills, or warm appliances

• Do not freeze — freezing can destroy the peptide structure and render it ineffective. If a vial has accidentally been frozen, do not use it

• Keep vials upright to minimise contact between the solution and the rubber stopper

• Never return a drawn dose to the vial — if a dose has been drawn and not used, discard it

Disclaimer

This calculator is provided for informational and educational purposes only. It is not intended to constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional before using any peptide product.