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PeptideHub

Peptide Reconstitution Calculator

Enter your vial size and bacteriostatic water volume to instantly compute the reconstituted concentration (mcg/mL) and the exact number of insulin-syringe units to draw for any target dose. Use this tool every time you open a new vial to avoid measurement errors.

Common research range for BPC-157: 250500 mcg, 2× daily, subcutaneous. Cycle: 4 weeks on / 2 off.

Educational use only. This calculator performs unit math on the values you provide and is not a substitute for medical advice. Verify every calculation independently.

Result

Concentration
2500 mcg / mL
Per syringe unit
25.00 mcg / unit
Draw to this mark
15.0 units (0.15 mL)
Dose, all units
375 mcg · 0.375 mg
Doses per vial
13.3 doses
Days per vial
6.7 days
Vials needed for 4-week cycle
5 vials

Numbers are computed from your inputs. Verify all calculations independently. Educational use only.

How to Use This Calculator

  1. Enter vial size: Input the peptide mass on the vial label in milligrams (e.g., 5 mg BPC-157). The calculator converts this to micrograms (mcg) automatically.
  2. Enter BAC water volume: Type the volume of bacteriostatic water you plan to add in mL. Common choices are 1 mL, 2 mL, or 3 mL. More water lowers concentration and makes small doses easier to read on a syringe.
  3. Enter your target dose: Input your research protocol dose in mcg. The calculator will compute how many insulin-syringe units correspond to this dose at the concentration you set.
  4. Select your syringe type: Choose U-100 (100 units/mL, the most common insulin syringe) or U-40 (40 units/mL, common in some veterinary contexts). This affects the unit-to-volume ratio.
  5. Read the results: The calculator returns concentration (mcg/mL), units to draw, volume in mL, doses per vial, and an estimated number of days the vial will last at that dose frequency.

Example Calculation

A researcher has a 5 mg BPC-157 vial and adds 2 mL of bacteriostatic water. The protocol calls for 250 mcg twice daily using a U-100 syringe.

StepCalculationResult
Convert vial to mcg5 mg × 1,0005,000 mcg
Concentration5,000 mcg ÷ 2 mL2,500 mcg/mL
mcg per U-100 unit2,500 ÷ 10025 mcg/unit
Units to draw for 250 mcg250 ÷ 2510 units
Doses per vial5,000 ÷ 25020 doses
Days at 2×/day20 ÷ 210 days

Reconstitution Reference Table

Common vial + BAC water combinations and resulting concentrations:

Vial SizeBAC WaterConcentrationmcg per U-100 unit
2 mg1 mL2,000 mcg/mL20 mcg
2 mg2 mL1,000 mcg/mL10 mcg
5 mg1 mL5,000 mcg/mL50 mcg
5 mg2 mL2,500 mcg/mL25 mcg
5 mg3 mL1,667 mcg/mL16.7 mcg
10 mg2 mL5,000 mcg/mL50 mcg
10 mg5 mL2,000 mcg/mL20 mcg

Frequently asked questions

What is peptide reconstitution?+

Reconstitution is the process of dissolving a lyophilized (freeze-dried) peptide powder in a liquid diluent — typically bacteriostatic water — to create an injectable solution. The powder is stable at room temperature; the liquid solution must be refrigerated.

How do I calculate reconstitution concentration?+

Concentration (mcg/mL) = vial peptide mass (mcg) ÷ diluent volume (mL). For example, a 5 mg (5,000 mcg) vial reconstituted with 2 mL gives 2,500 mcg/mL. This calculator performs that math instantly.

How many units do I draw for my dose?+

Units to draw = (dose mcg ÷ concentration mcg/mL) × syringe units per mL. For a U-100 syringe (100 units/mL): draw = dose ÷ (vial mcg ÷ mL) × 100. The calculator handles this automatically.

What diluent should I use for peptide reconstitution?+

Bacteriostatic water (sterile water with 0.9% benzyl alcohol) is the standard choice for research peptides. It is antimicrobial and extends the usable life of the reconstituted solution to approximately 30 days when refrigerated. Sterile water for injection can also be used but requires single use.

Does the order of reconstitution matter?+

Yes. Always inject the diluent slowly against the inside wall of the vial rather than directly onto the peptide cake. Swirl gently — never shake — to avoid denaturing the peptide. Let it sit for 1–2 minutes if it does not dissolve immediately.

How long does reconstituted peptide last?+

Most reconstituted peptides remain stable for approximately 30 days when refrigerated at 2–8°C and protected from light. Light-sensitive peptides such as GHK-Cu should be stored in amber vials or wrapped in foil.

Can I use the same calculator for any peptide?+

Yes. The reconstitution math is identical regardless of peptide identity — only the mass and volume matter. The peptide selector in this calculator pre-fills common protocol doses for convenience, but all fields are fully editable.