Peptide Reconstitution Concentration Calculator
Work out the concentration of your reconstituted peptide solution. Enter the amount of peptide in the vial and the volume of water used to get an instant mg/mL reading.
This is the concentration of your reconstituted solution. This tool calculates concentration only, it does not calculate or display an injection or draw volume.
This calculator is a reference tool for laboratory research purposes only. It does not constitute dosing advice for human or animal use. Always follow your institution’s protocols and verify calculations independently.
What is a peptide reconstitution calculator?
Research peptides are typically supplied as a freeze-dried (lyophilized) powder sealed in a vial. Before that powder can be measured, it has to be dissolved in a liquid, almost always bacteriostatic water, to create a solution with a known concentration. A reconstitution calculator takes two numbers you already know — how much peptide is in the vial and how much water you added — and converts them into a single answer: the concentration of the resulting solution, in mg/mL.
It replaces manual arithmetic (and the rounding errors that come with it) with an instant readout, so the same calculation can be repeated consistently across a research protocol.
How reconstitution math works
1. Find the concentration
Divide the total peptide mass in the vial (mg) by the volume of water you added (mL). That gives you mg per mL, this is what the calculator above shows you.
2. Apply your own protocol
Once you know the concentration, your institution’s protocol documentation determines how any given amount is measured out from that solution. This tool stops at concentration and does not calculate or display an administration volume.
Why accurate concentration matters
A small error in reconstitution math compounds every time the same vial is drawn from. Using too little water concentrates the solution above the intended figure; using too much dilutes it below. Because a single vial is usually drawn from repeatedly across a protocol, an error in the initial calculation doesn’t just affect one measurement, it affects every measurement taken from that vial.
Working from a fixed, calculated concentration rather than estimating by eye keeps every measurement from the same vial consistent, which matters for reproducibility in any research setting.
Typical vial sizes by peptide
Vial sizes vary by supplier and product, but these are common amounts for widely studied research peptides. Always use the amount printed on your specific vial rather than assuming a standard size.
| Peptide | Common vial size |
|---|---|
| BPC-157 | 5 mg |
| TB-500 | 5 mg |
| Semaglutide | 5 mg |
| Tirzepatide | 5–10 mg |
| Retatrutide | 5–10 mg |
| CJC-1295 / Ipamorelin | 5 mg |
| NAD+ | 100 mg |
| Epitalon | 50 mg |
How to use this calculator
- Enter the peptide amount printed on your vial, in milligrams.
- Enter the water volume you used to reconstitute it, in milliliters.
- Read your result — the concentration figure updates instantly in mg/mL.
Frequently asked questions
What is bacteriostatic water and why does the amount matter?
Bacteriostatic water (BAC water) is sterile water containing 0.9% benzyl alcohol, used to reconstitute lyophilized peptides. The amount you add directly sets the concentration of your solution — more water means a more dilute solution, less water means a more concentrated one.
Why does the concentration figure matter?
Research peptides are typically supplied as freeze-dried powder in a sealed vial. Reconstitution math converts the total mass in that vial into a concentration (mg/mL), which is the figure your own protocol documentation then uses.
Can I use this calculator for any peptide?
The math is the same regardless of which peptide is in the vial, since it’s based purely on mass and volume. What differs between peptides is the typical vial size and the water volume used to reconstitute it, both of which you enter yourself.
Is this calculator a substitute for a lab protocol?
No. This tool is provided as a quick reference for research calculations only. Always follow your institution’s established protocols and independently verify any calculation before use in research.
Quick Conversion Key
Common mg ↔ mcg conversions.
| Milligrams (mg) | Micrograms (mcg) |
|---|---|
| 0.1 mg | 100 mcg |
| 0.25 mg | 250 mcg |
| 0.5 mg | 500 mcg |
| 1 mg | 1,000 mcg |
| 2 mg | 2,000 mcg |
| 5 mg | 5,000 mcg |
| 10 mg | 10,000 mcg |