Peptide Reconstitution Calculator

Enter your vial size and the amount of bacteriostatic water you are adding. The calculator gives you the exact concentration in mcg/ml and the precise units to draw for your dose.

Quick-fill by compound

mg
ml
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Results

Concentration

2500 mcg/ml

2.5 mg/ml

Volume to inject

0.1 ml

per dose

Units on insulin syringe (U-100)

10 units

on a standard 100-unit insulin syringe

Doses per vial

20 doses

at 250 mcg each

How this is calculated

5mg × 1,000 = 5000 mcg total

5000 ÷ 2ml = 2500 mcg/ml

250 mcg ÷ 2500 = 0.1 ml

0.1 ml × 100 = 10 units

Disclaimer: This calculator is provided for informational purposes only. Always verify results against your specific vial labelling before use. Peptidy does not provide medical advice — consult a qualified healthcare professional before beginning or modifying any protocol. Use of research peptides may be subject to legal restrictions in your jurisdiction.

How reconstitution works

Step 01

Concentration

Divide the total peptide content (mg × 1,000 to get mcg) by the volume of BAC water added (ml). The result is your concentration in mcg/ml.

Step 02

Injection volume

Divide your desired dose (mcg) by the concentration (mcg/ml). The result is the exact volume to draw in millilitres.

Step 03

Syringe units

Multiply the volume in ml by 100. A U-100 insulin syringe holds 1ml = 100 units, so 0.1ml = 10 units, 0.05ml = 5 units.

Worked example: 5mg BPC-157 + 2ml BAC water, 250mcg dose

  • 5mg × 1,000 = 5,000 mcg total in vial
  • 5,000 mcg ÷ 2ml = 2,500 mcg/ml concentration
  • 250 mcg ÷ 2,500 mcg/ml = 0.1ml to inject
  • 0.1ml × 100 = 10 units on an insulin syringe
  • 5,000 mcg ÷ 250 mcg = 20 doses per vial

Frequently asked questions

How much BAC water should I add to a 5mg BPC-157 vial?

The most common approach is 2ml, which gives a concentration of 2,500 mcg/ml. A 250mcg dose then equals 0.1ml (10 units on a U-100 insulin syringe). If you prefer smaller injection volumes, use 1ml for 5,000 mcg/ml — your dose volume halves to 5 units.

What is the formula for peptide concentration?

Concentration (mcg/ml) = [Vial amount in mg × 1,000] ÷ [ml of BAC water added]. For example: 5mg × 1,000 = 5,000 mcg ÷ 2ml = 2,500 mcg/ml.

How do I convert injection volume to units on an insulin syringe?

A standard U-100 insulin syringe holds exactly 1ml = 100 units. To convert: Units = Volume in ml × 100. So 0.1ml = 10 units, 0.2ml = 20 units, 0.05ml = 5 units.

How many units is 250mcg of BPC-157?

It depends on your reconstitution concentration. At 2,500 mcg/ml (5mg vial + 2ml BAC water): 250 ÷ 2,500 = 0.1ml = 10 units. At 5,000 mcg/ml (5mg + 1ml): 250 ÷ 5,000 = 0.05ml = 5 units.

Can I use sterile water instead of bacteriostatic water?

Bacteriostatic water (BAC water) contains 0.9% benzyl alcohol, which inhibits microbial growth. This allows reconstituted peptides to be stored refrigerated for 4–6 weeks. Sterile water for injection has no preservative — use within 24 hours and discard the rest. For multi-dose vials, BAC water is strongly preferred.

How long does reconstituted peptide last in the fridge?

Reconstituted peptides stored in BAC water typically remain viable for 4–6 weeks at 2–8°C (36–46°F), kept away from light. Label each vial with the date of reconstitution. Do not freeze reconstituted peptides — freeze-thaw cycles degrade the compound.

How do I add BAC water to a peptide vial correctly?

Draw the BAC water into your syringe. Insert the needle into the vial at an angle so it points toward the glass wall (not directly at the powder). Slowly release the water down the side of the vial. Never squirt water directly onto lyophilised peptide — it damages the molecular structure. Once added, gently roll the vial between your palms. Do not shake.

Log every reconstitution in Peptidy

Store your vial concentration, track doses against it, and never lose track of what you injected or when.