What Is a Peptide Calculator?
A Peptide Calculator is a tool used to calculate important values related to peptides, including molecular weight, amino acid composition, dosage amounts, and reconstitution volumes. Whether you're a researcher, scientist, or medical professional, this calculator saves time and reduces the risk of dosage errors.
What Can This Calculator Help You With?
Depending on your needs, a peptide calculator can help you determine:
- Molecular weight of a peptide based on its amino acid sequence
- Reconstitution volume — how much bacteriostatic water or solvent to add to a lyophilized peptide
- Dosage per injection based on vial size and desired dose in mcg
- Number of doses available per vial
- Concentration of a reconstituted peptide solution
Key Peptide Terms You Should Know
Lyophilized Peptide Most research peptides come in a freeze-dried (lyophilized) powder form, measured in milligrams (mg). They must be reconstituted with a liquid before use.
Bacteriostatic Water (BAC Water) The most commonly used solvent for reconstituting peptides. It contains a small amount of benzyl alcohol to prevent bacterial growth.
Mcg vs Mg Peptide doses are often measured in micrograms (mcg). There are 1,000 mcg in 1 mg — a distinction that's critical for accurate dosing.
How to Use the Peptide Calculator
- Enter the vial size — the total amount of peptide in your vial (e.g., 5mg)
- Enter the reconstitution volume — how much BAC water you plan to add (e.g., 2ml)
- Enter your desired dose in mcg
- Click Calculate to instantly see the volume per injection and total doses available
Peptide Reconstitution Example
| Vial SizeBAC Water AddedConcentrationDose (250mcg)Volume to Draw | ||||
| 5mg | 2ml | 2,500mcg/ml | 250mcg | 0.10ml (10 IU) |
| 10mg | 2ml | 5,000mcg/ml | 500mcg | 0.10ml (10 IU) |
Why Accurate Peptide Calculations Matter
Getting peptide dosages wrong — even slightly — can affect research outcomes or lead to unintended results. Using a calculator ensures:
- Precision in every dose drawn
- Consistency across multiple uses of the same vial
- Less waste by knowing exactly how many doses a vial contains
- Safer handling of sensitive compounds
Frequently Asked Questions
How much BAC water should I add to my peptide vial? It depends on your desired concentration. A common approach is adding 1–2ml of BAC water to a 5mg vial, giving a concentration of 2,500–5,000 mcg/ml.
Can I use sterile water instead of BAC water? Sterile water can be used but has a much shorter shelf life once opened. BAC water is preferred for multi-use vials.
How long does a reconstituted peptide last? Most reconstituted peptides remain stable for 4–6 weeks when refrigerated at 2–8°C and kept away from light.
What is the molecular weight of a peptide used for? Molecular weight helps researchers calculate molar concentrations and is essential for precise scientific measurements.
This calculator is intended for research and informational purposes only. Always consult a qualified medical or scientific professional before handling peptides.