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Peptide Dosage Calculator
Peptide Dosage Calculator — How to Reconstitute and Dose Peptides Accurately
Getting peptide dosage right is not guesswork. When working with research peptides, an error in reconstitution or volume measurement can compromise an entire experiment. This calculator removes that guesswork — enter your peptide amount, bacteriostatic water volume, and desired dose, and it tells you exactly how much to draw on your syringe.
All products at Patriot Peptides are supplied strictly for laboratory and scientific research use only. They are not intended for human consumption, veterinary use, or clinical application.
What This Calculator Does
This tool covers the full workflow from reconstitution to injection volume to supply planning across four sections:
Peptide Information — enter the peptide amount in the vial (mg) and vial size (mL).
Reconstitution — enter the amount of bacteriostatic water you are adding. The calculator instantly shows your final concentration in mg/mL.
Dosage Calculation — enter your desired dose in mcg or mg. The calculator outputs the exact injection volume in mL and shows the corresponding mark on your selected syringe type.
Dosage Frequency — enter how often you are dosing and for how many days. The summary shows total peptide needed, number of vials required, and estimated cost.
How to Use the Calculator
Step 1 — Enter your peptide amount and vial size. Type in the milligram amount printed on your vial. For example, a standard BPC-157 vial is 5 mg. Enter the vial’s stated volume capacity in the Vial Size field.
Step 2 — Enter your BAC water amount. Type how many mL of bacteriostatic water you are adding. A common starting point is 1–2 mL. The Final Concentration field auto-calculates in mg/mL.
Step 3 — Enter your desired dose. Type your target dose and select the unit — mcg or mg. Most research peptide doses are expressed in micrograms. The Injection Volume field shows exactly how many mL to draw.
Step 4 — Select your syringe type. Choose 1 mL, 3 mL, 5 mL, or 10 mL. The syringe visual updates to show the fill level and the exact unit marking on a 100-unit insulin syringe. Toggle between Units and mL views depending on how your syringe is marked.
Step 5 — Set frequency and duration. Select dosing frequency and total days. The summary cards show total peptide needed, vials required, and estimated cost.
Peptide Reconstitution Explained
Research peptides are supplied in lyophilized (freeze-dried) powder form. Before use in a laboratory setting, they must be reconstituted — dissolved in a sterile liquid. Bacteriostatic water (sterile water with 0.9% benzyl alcohol as a preservative) is the standard solvent because it keeps the solution stable for weeks when refrigerated.
The reconstitution ratio you choose directly determines your working concentration:
| Peptide Amount | BAC Water Added | Final Concentration | Volume per 250 mcg dose |
|---|---|---|---|
| 5 mg | 1 mL | 5 mg/mL | 0.05 mL (5 units) |
| 5 mg | 2 mL | 2.5 mg/mL | 0.10 mL (10 units) |
| 5 mg | 5 mL | 1 mg/mL | 0.25 mL (25 units) |
| 5 mg | 10 mL | 0.5 mg/mL | 0.50 mL (50 units) |
Less BAC water gives a more concentrated solution — smaller injection volumes but harder to measure precisely. More BAC water gives easier-to-measure volumes but means you go through vials faster. Most researchers find 1–2 mL a practical middle ground for a 5 mg vial.
How to Read a Syringe for Peptide Dosing
The most common syringe used in peptide research is the 1 mL insulin syringe marked in 100 units, where 100 units = 1 mL, meaning 1 unit = 0.01 mL. This calculator shows you the exact unit number to draw to, eliminating conversion errors.
For example: if you reconstituted 5 mg in 2 mL of BAC water (2.5 mg/mL) and want a 250 mcg dose, the injection volume is 0.10 mL — which is the 10 unit mark on a 100-unit insulin syringe.
Always use a fresh syringe for each draw. Draw slowly to avoid air bubbles. Wipe the vial septum with an alcohol swab before each needle insertion.
Common Peptides and Typical Research Doses
The following reflects doses commonly reported in published preclinical studies — for research planning reference only.
| Peptide | Typical Research Dose | Frequency in Studies | Route |
|---|---|---|---|
| BPC-157 | 200 – 500 mcg | Once or twice daily | Subcutaneous |
| TB-500 | 2.5 – 5 mg | 1–2x per week | Subcutaneous |
| CJC-1295 No DAC | 100 – 200 mcg | Twice daily | Subcutaneous |
| Ipamorelin | 100 – 300 mcg | 2–3x daily | Subcutaneous |
| GHRP-2 | 100 – 300 mcg | 2–3x daily | Subcutaneous |
| Epithalon | 5 – 10 mg | Daily, cyclical | Subcutaneous |
| GHK-Cu | 1 – 2 mg | Daily | Subcutaneous |
| AOD-9604 | 300 – 500 mcg | Once daily | Subcutaneous |
Browse the full range of research-grade compounds at Patriot Peptides Library.
BAC Water vs Sterile Water
Both can reconstitute peptides. The difference matters for storage:
Bacteriostatic water contains 0.9% benzyl alcohol, which prevents bacterial growth. A reconstituted vial stored at 2–8°C remains stable for 4–6 weeks. This is the standard choice for most peptide research.
Sterile water for injection has no preservative. A reconstituted solution should be used within 24 hours. Use this when the compound is known to be incompatible with benzyl alcohol.
Peptide Storage Guidelines
Unreconstituted peptides should be stored at -20°C, away from light and moisture. Properly stored, most peptides remain stable for 24 months or longer.
Reconstituted peptides should be refrigerated at 2–8°C. Do not freeze a reconstituted solution — repeated freeze-thaw cycles damage the peptide chain.
Always label vials with the reconstitution date. Use a clean needle and alcohol-swabbed septum every time. Never reuse a syringe that has contacted biological material.
Why Accurate Dosing Matters in Peptide Research
In preclinical research, dose consistency is one of the most critical variables. A study administering 250 mcg versus 500 mcg will see meaningfully different receptor binding profiles. Dosing errors accumulated across a multi-week study introduce noise into data and make results harder to reproduce. This calculator gives researchers a fast, reliable way to confirm their syringe draw volume before every administration.
Frequently Asked Questions
What is the difference between mcg and mg when dosing peptides?
1 mg = 1,000 mcg. Most research peptides are dosed in micrograms because the active amounts are small. This calculator accepts both units — select the correct one from the dropdown.
How do I calculate injection volume manually?
Injection Volume (mL) = Dose (mg) ÷ Concentration (mg/mL). If you reconstituted 5 mg in 2 mL, concentration is 2.5 mg/mL. For a 250 mcg (0.25 mg) dose: 0.25 ÷ 2.5 = 0.10 mL.
Why does my syringe show units instead of mL?
Insulin syringes are marked in IU where 100 units = 1 mL. So 10 units = 0.10 mL, 25 units = 0.25 mL. The calculator’s Units toggle converts your mL volume to the equivalent syringe mark automatically.
How long does a reconstituted peptide vial last?
Reconstituted with bacteriostatic water and stored at 2–8°C, most peptides remain stable for 4–6 weeks. Label vials with the reconstitution date and discard after the recommended window.
What syringe size should I use?
For injection volumes under 1 mL, a 1 mL insulin syringe with a 28–31 gauge needle is standard. For larger volumes, a 3 mL syringe gives better resolution on the measurement scale.
Where can I buy research peptides with verified purity?
Patriot Peptides supplies pharmaceutical-grade compounds manufactured in US cGMP-certified facilities, with third-party Certificates of Analysis for every batch. Browse the full peptide library here.
