Reconstitution Calculator

Work out the concentration of a reconstituted research peptide, and how much mass any given volume contains. Enter the vial mass and your diluent volume — or work backwards from a concentration you need to hit.

Research Use Only. This tool performs laboratory concentration arithmetic (mass ÷ volume). It does not select, recommend, or calculate an amount for administration. Products supplied by Omnix Peptides are intended for in vitro research and laboratory use only — not for human consumption, animal consumption outside approved preclinical research, therapeutic application, or clinical use.
Step 1Vial mass

The total peptide mass printed on the vial label.

mg
Step 2Diluent volume

Bacteriostatic water or other diluent added to the vial.

mL

Resulting concentration

Enter a vial mass and diluent volume

Mass per volume

Once you enter values above, this table shows how much peptide mass each volume of the reconstituted solution contains.
VolumeContains

Volume for a given mass

Enter a mass to find the volume of this solution that contains it.

—

Volume and mass are not the same thing. The same volume drawn from two differently-reconstituted vials contains different amounts of peptide — concentration is what links them.

How to use this calculator

The calculator turns two values from your vial into the one number that governs everything downstream: concentration.

Find concentration

Enter the mass printed on the vial (in mg) and the volume of diluent you added (in mL). The result is the concentration in mg/mL and mcg/mL, plus a table showing how much peptide mass each volume of that solution contains.

Find diluent volume

Work in reverse: enter the vial mass and the concentration you want to end up with, and the calculator returns the diluent volume to add. This is the more useful direction when you need several vials to share one working concentration.

Worked example

A 10 mg vial reconstituted with 2 mL of bacteriostatic water:

ValueResult
Vial mass10 mg
Diluent added2 mL
Concentration5 mg/mL
0.1 mL contains500 mcg
0.5 mL contains2.5 mg

The arithmetic: 10 mg ÷ 2 mL = 5 mg/mL. Then 5 mg/mL × 0.1 mL = 0.5 mg, or 500 mcg.

Choosing a diluent volume

More diluent produces a lower concentration, which means larger volumes for the same mass — easier to measure accurately at small scales. Less diluent concentrates the solution, which conserves vial space but makes small-mass measurement less precise, since a small volumetric error carries more mass with it.

Reconstituted solutions also have a shorter stability window than lyophilized powder. See the powder and storage guide and the diluent comparison for handling considerations, and the reconstitution math guide for the underlying calculations in full.

Frequently asked questions

What does mg/mL mean?

Milligrams of peptide per millilitre of solution. It is the ratio that links mass to volume: multiply a volume by the concentration to get the mass that volume contains.

How do I convert between mg and mcg?

1 mg equals 1,000 mcg. The calculator reports both so small quantities stay readable.

Does the diluent volume change the total peptide mass?

No. The vial contains a fixed mass regardless of how much diluent is added. Diluent volume changes the concentration, and therefore how much volume contains any given mass.

What is the volume-for-mass lookup for?

It answers the inverse of the table: given a mass you need, it returns the volume of your solution that contains it. Useful when a protocol specifies mass and you need the corresponding volume at your particular concentration.

Why would I use the reverse calculation?

To standardise. If an experimental design calls for a fixed working concentration across vials of different strengths, the reverse calculation gives the diluent volume each vial needs to reach it.

Does this calculator account for the volume of the lyophilized powder itself?

No. It treats the final volume as equal to the diluent volume added, which is the standard simplification in reconstitution arithmetic. The powder's displaced volume is negligible at these masses.

Does this tool calculate an amount to administer?

No. It performs concentration and mass-per-volume arithmetic only. It does not select, recommend, or compute any quantity for administration to humans or animals.

Compound-specific calculators

Each of these pre-loads that compound's available vial strengths. Compounds supplied only as capsules or liquid sprays are not listed — they ship ready-to-use and are not reconstituted.

Important Notice — Research Use Only. This calculator is a laboratory arithmetic tool provided for informational purposes in a research context. Products supplied by Omnix Peptides are intended for in vitro research and laboratory use only. They are not for human consumption, are not for animal consumption outside of approved preclinical animal research, are not intended to diagnose, treat, cure, or prevent any disease, and have not been approved by the FDA for any therapeutic application. Verify all values against the vial label and your own protocol before relying on a result.