Research Tool

Peptide Reconstitution
& Dosage Calculator

Enter your vial size, BAC water volume, and desired dose. Instantly see concentration, injection volume, and the exact units to draw on a U-100 syringe, with direct links to order the matching Stackpure product.

12 Peptide Presets
4 Syringe Types
U-100 Primary Format
RUO Research Only

Calculator Inputs

Quick-fill a peptide preset:

Reconstitution

Amount printed on the vial label (e.g. 5mg, 10mg)

Bacteriostatic water volume you'll inject into the vial

Dosage

Target dose in micrograms (1mg = 1000mcg)

Most insulin syringes are U-100 (100 units = 1mL)

Results

Concentration — mcg / mL

Peptide per mL of solution

Injection Volume — mL per dose

Volume to draw for your dose

Syringe Units to Draw — units on barrel

Pull plunger to this line

Doses per Vial — full doses

At your chosen dose amount

Select a preset or enter values, then press Calculate

Reading a U-100 Syringe

4 things every researcher needs to know

The numbers on the barrel are units. On the standard U-100 insulin syringe, 100 units = 1mL.

Find the unit markings

Each line on the barrel is units. Major marks appear at 10, 20, 30 … 100. Minor marks every 2 units. The numbers represent volume, not mass.

Draw to the correct line

Pull the plunger until the bottom of the rubber stopper sits exactly on your target unit number. Small doses mean small volumes. Use magnification if needed.

Units ≠ mg ≠ mcg

Syringe units measure volume only. This calculator converts your mcg dose to units based on the concentration of your reconstituted solution.

Tiny dose? Add more BAC water

If your calculated volume is under 5 units, increase your BAC water volume to dilute the concentration. This makes measuring more precise and reduces injection error.

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Frequently Asked Questions

How do I reconstitute a lyophilized peptide vial?

Reconstituting a peptide means dissolving the freeze-dried (lyophilized) powder in bacteriostatic water (BAC water). Using a clean syringe, draw 1–2 mL of BAC water and inject it slowly down the inside wall of the vial. Never inject directly onto the powder. Gently swirl, do not shake. Store at 2–8°C after reconstitution and use within 2–4 weeks.

What is bacteriostatic water and why is it used for peptides?

Bacteriostatic water (BAC water) is sterile water containing 0.9% benzyl alcohol as a preservative. The benzyl alcohol inhibits bacterial growth, allowing the reconstituted peptide solution to remain stable for multi-use research over several weeks when refrigerated. Standard sterile water has no preservative and must be used immediately or discarded.

How many units do I draw on a U-100 insulin syringe?

On a U-100 insulin syringe, 100 units = 1 mL. To calculate: (desired dose mcg ÷ concentration mcg/mL) × 100 = units to draw. Example: 250 mcg ÷ 2500 mcg/mL × 100 = 10 units. Use the Stackpure calculator to compute this automatically from your vial size and BAC water volume.

How much BAC water should I add to a 5mg peptide vial?

For a 5mg (5000 mcg) vial, adding 2 mL of BAC water gives a concentration of 2500 mcg/mL, the most common working concentration for standard doses. For very small doses (under 100 mcg), consider adding 2.5 mL to reach 2000 mcg/mL, making the injection volume easier to measure precisely on the syringe barrel.

How long does a reconstituted peptide remain stable?

A peptide reconstituted in bacteriostatic water is typically stable for 2–4 weeks when stored refrigerated at 2–8°C, protected from light. Lyophilized (freeze-dried) peptides stored at −20°C maintain stability for 1–2 years. Once reconstituted, do not refreeze the solution.