Free laboratory research tool

Peptide Reconstitution Calculator

Use this free peptide reconstitution calculator to work out a nominal solution concentration in mg/mL and micrograms/mL. Enter the labeled compound amount and solution volume to see the math clearly.

For laboratory research only. This tool calculates concentration; it does not determine a suitable solvent, a safe concentration, a dose, or an injection volume. Follow the supplied product specification and your laboratory protocol.

Calculate solution concentration

Start with the amount of compound in one vial, not the vial’s physical size. No suggested mixing quantities are preselected.

Labeled compound amount per vial

mgmicrograms

Use the amount stated on the supplied label. 1 mg = 1,000 micrograms.

Solution volume (mL)

Use a measured final volume for the most accurate calculation.

What does your volume represent?Measured final solution volumeDiluent volume added — estimate only

If using water or another diluent added, the result assumes that added volume equals the final solution volume. The actual final volume may differ.

Calculate concentrationClear

Keep this calculator on your home screen

Save the free tool for quick access. No account or App Store download is needed.

iPhone or iPad — save with Safari

1. Open this calculator page in Safari.
2. Open the Share menu (under the More or Page Menu button in some layouts).
3. Choose Add to Home Screen. If it is missing, use Edit Actions to add it.
4. Turn on Open as Web App if offered, then tap Add.

Your new home-screen icon opens the calculator. Apple’s home-screen instructions.

Android — save with Chrome

Open this page in Chrome and open the browser menu. Choose Install and create shortcut, then Create shortcut, name it, and tap Add. Some versions instead show Add to Home screen. Google’s shortcut instructions.

Internet access is required to load this version. Calculations happen in your browser; the tool does not submit your entered amounts. Saving the page does not install a native iOS app.

How the reconstitution calculation works

Concentration (mg/mL) = compound amount (mg) ÷ final solution volume (mL). Multiply mg/mL by 1,000 to express the same concentration in micrograms/mL. Adding more diluent changes the concentration, not the original labeled amount of compound.

The following examples illustrate arithmetic only. They are not mixing recommendations for any product.

Examples of nominal laboratory concentration

Compound amount	Final volume	Concentration
10 mg	1 mL	10 mg/mL
10 mg	2 mL	5 mg/mL
20 mg	2 mL	10 mg/mL

Bacteriostatic water and peptide reconstitution

“BAC water” is a common abbreviation for bacteriostatic water. Astra Biolabs’ bacteriostatic-water listings identify water with 0.9% benzyl alcohol. It is a diluent; it does not supply peptide mass. A 10 mL water container is not a 10 mg peptide vial.

Peptide solubility depends on the compound and formulation. Bacteriostatic water is not automatically suitable for every research material. Confirm the solvent, storage conditions, container capacity, and handling requirements from the supplied documentation before preparing a laboratory solution. This calculator does not choose them for you.

Common questions

How much bacteriostatic water should I add?

There is no universal amount. Your laboratory protocol and product specification determine the solvent and target concentration. This calculator shows the concentration resulting from an amount and volume you supply; it does not recommend a water volume.

Is mg per vial the same as mg/mL?

No. Milligrams per vial describe an amount of compound. Milligrams per milliliter describe concentration after a solution volume is established. For example, 10 mg in a final volume of 2 mL has a nominal concentration of 5 mg/mL.

Can I use this for a peptide blend?

You can calculate total blend concentration from the combined labeled mass. To calculate an individual component’s concentration, use that component’s labeled mass with the same final volume. Do not assume components are present in equal amounts.

Can this convert IU to mg or syringe units?

No. International units describe biological activity and cannot be converted to mass without a substance-specific relationship. This calculator reports mass concentration only and does not calculate doses or syringe measurements.

What if my item is already a liquid?

Use the supplied label to establish whether the listing is a powder or a prepared solution. Do not assume a liquid needs reconstitution. If concentration or amount per container is unclear, contact Astra Biolabs before using this calculation.

Does the result tell me how long a solution will last?

No. Stability and storage requirements are specific to the compound, formulation, solvent, and handling conditions. Use the product documentation and laboratory protocol; the calculator does not establish a shelf life.

Related research resources

Peptide names and documentationResearch libraryBacteriostatic Water 10mL specificationsBacteriostatic Water 30mL specificationsAsk a product-specification question

Reference: Sigma-Aldrich peptide solubility guidelines. Solvent guidance is compound-specific; the arithmetic tool does not replace it.

Updated October 8, 2026. For laboratory research only. Not for human or veterinary use. See our research-use policy.