Research tool
Peptide Reconstitution Calculator
Work out the concentration and the volume to withdraw for a reconstituted research peptide. Enter the mass in the vial, how much bacteriostatic water you plan to add, and any target amount — the calculator does the arithmetic. It recommends no amount; all figures are for laboratory research use only.
Inputs
This tool performs reconstitution arithmetic on the values you enter. It is not a dosing protocol and does not recommend any amount. All compounds are supplied for laboratory research use only — not for human or animal use.
The reconstitution formula
Reconstitution is dividing a fixed mass of peptide across a volume of water. Two calculations do all the work:
Concentration (mg/mL) = vial mass (mg) ÷ water added (mL)
Draw volume (mL) = target amount (mg) ÷ concentration (mg/mL)
A worked example
The numbers below are arbitrary, chosen only to show the arithmetic — they are not a recommended amount. Suppose a vial holds 5 mg of peptide and you add 2 mL of bacteriostatic water. The concentration is 5 ÷ 2 = 2.5 mg/mL (2,500 mcg/mL). To measure out any target amount — say 0.25 mg — the draw volume is 0.25 ÷ 2.5 = 0.1 mL. A fully dissolved 5 mg vial contains about 20 aliquots of that size.
Frequently asked questions
How do you reconstitute a lyophilised research peptide?
Reconstitution means dissolving a freeze-dried (lyophilised) peptide back into liquid so a known amount can be measured out. Bacteriostatic or sterile water is added slowly down the inside wall of the vial — never sprayed directly onto the powder — and the vial is gently swirled, not shaken, until the solution is clear. The volume of water added sets the concentration: the same vial dissolved in less water is more concentrated, and in more water is more dilute.
What is the reconstitution formula?
Concentration (mg/mL) = peptide mass in the vial (mg) ÷ volume of water added (mL). To find the volume to withdraw for a target amount: draw volume (mL) = target amount (mg) ÷ concentration (mg/mL).
How much bacteriostatic water should be added to a vial?
There is no single correct volume — it is chosen for convenience. More water makes each measured amount easier to read on the syringe but dilutes the solution; less water concentrates it. Common working volumes are 1, 2, 3, or 5 mL. The calculator lets you compare volumes side by side so you can pick one that puts your target amount at an easy-to-read point on the syringe.
What does 'draws per vial' mean?
It is simply the vial mass divided by the target amount per draw — an estimate of how many equal aliquots of that size a fully dissolved vial contains. It ignores residual dead volume in the syringe and vial, so treat it as an upper-bound estimate for planning.
Does the amount of water change how much peptide is in the vial?
No. The total peptide mass in the vial is fixed by the product. Adding more or less water only changes the concentration (mg per mL), and therefore the volume you withdraw to measure out a given amount — not the total amount available.
Are these calculations a dosing recommendation?
No. The calculator performs arithmetic on values you enter and does not recommend any amount, frequency, or route. All CertaPeptides compounds are supplied for laboratory research use only and are not for human or animal use. Nothing on this page is medical guidance.
This calculator is a laboratory convenience tool that performs arithmetic on the values you enter. It does not recommend any amount, frequency, or route of administration and is not medical guidance. All products sold by CertaPeptides (CERTALAB S.R.L.) are intended for laboratory research use only and are not for human or animal consumption. CertaPeptides is a reseller, not a manufacturer.