Peptide Calculator
Calculate syringe units from vial amount, reconstitution volume, and target amount. Use the quick lookup pages for instant references, or use this calculator for exact custom math.
To have a dose of 0.25 mg pull the syringe to
250 mcg (μg)
10 units
Example only. Use the buttons to preload math, then adjust the setup to match your own vial and reconstitution details.
Disclaimer
This is a concentration and volume calculator provided for informational and research purposes only. It performs unit-conversion math from the values you enter — it does not recommend any peptide, amount, or regimen, is not medical advice, and takes no position on the use of any substance. Many peptides are sold for laboratory research only, are not approved for human use, and may be regulated where you live. Consult a qualified professional and follow all applicable laws. Calculation accuracy depends on the values you enter.
Popular peptide examples on this page are concentration-math references only. Trial outcomes, label windows, and formulation context should not be collapsed into a universal reconstitution recommendation.
📐 How is this calculated?
Step 1: Concentration
5 mg ÷ 2 ml = 2.50 mg/ml
Step 2: mg per Unit
2.50 mg/ml ÷ 100 units/ml = 0.0250 mg/unit
Step 3: Units Needed
0.25 mg ÷ 0.0250 mg/unit = 10 units
After you calculate: drawing and storing the dose
A U-100 syringe to draw the units above, and cold storage for the vial once it is reconstituted — most reconstituted peptides need 2–8°C and do not tolerate freezing, so a dedicated fridge is the relevant appliance here, not a freezer. Bacteriostatic water is a pharmacy item and is not linked here.
PeptideClock may earn a commission from qualifying purchases via links on this page, at no additional cost to you. Product links are general lab and handling equipment, not medical advice — See our disclaimer.
1 mL · 100-unit
BH Supplies U-100 Insulin Syringes — 31G, 1 mL (100 pk)
A 1 mL (100-unit) U-100 syringe with a 31G × 5/16″ (8mm) needle — the most versatile size, with the most range for larger draws. A long-standing favorite for general reconstituted-peptide measurement work.
View on AmazonThermoelectric · AC/DC/USB
Cooluli 4 L Mini Fridge
A compact 4-liter thermoelectric fridge — a common way to keep reconstituted vials in a dedicated cold space away from a busy kitchen fridge. Runs on AC, 12V DC, and USB.
View on AmazonCompressor cooling
BLACK+DECKER 1.7 cu ft Compact Refrigerator
A 1.7 cubic-foot compact refrigerator with compressor cooling, so its temperature is set on the appliance rather than tracking the room as a thermoelectric cooler does. Adjustable dial thermostat. Keep vials clear of the freezer compartment.
View on AmazonUnderstanding Peptide Dosing
Accurate dosing is critical when working with reconstituted peptides. This calculator helps you determine the exact number of units to draw on your insulin syringe for your desired dose, eliminating guesswork and reducing the risk of dosing errors.
mcg to units lookup
Use the static lookup tables when you already know your concentration.
Stack checker
Check how two or more peptides are handled together before you plan a schedule.
Syringe dosing chart
Scan example rows for common concentration and U-100 unit pairings.
Printable cheat sheet
Keep a condensed U-100 reference handy for print or quick bench-side review.
How to Use This Calculator
- Select Peptide Strength: The amount of peptide powder in your vial (usually 5mg, 10mg, etc.)
- Select Reconstitution Volume: How much bacteriostatic water or saline you added
- Select Desired Dose: Your target amount per dose in mg
- Select Syringe Size: Choose your insulin syringe capacity (30, 50, or 100 units)
The calculator instantly shows your concentration (mg/ml), mg per unit, and the exact units to draw. Use the visual syringe guide to verify the units to draw.
Common Syringe Sizes
100-unit (1ml)
Most common size. Each unit = 0.01ml. Best for larger doses and higher concentrations.
50-unit (0.5ml)
Each unit = 0.01ml. Ideal for medium doses. Offers finer control than 100-unit.
30-unit (0.3ml)
Each unit = 0.01ml. Best for very small doses and low concentrations. Finest precision.
Example Calculation Contexts
| Peptide | Example Amount | Example Recon | Units (100-unit) |
|---|---|---|---|
| Tirzepatide | 2.5 mg | 10mg / 2ml | 50 units |
| Semaglutide | 0.5 mg | 5mg / 2ml | 20 units |
| BPC-157 | 250 mcg | 5mg / 2ml | 10 units |
| Ipamorelin | 200 mcg | 5mg / 2ml | 8 units |
Example math only. These rows show concentration conversion context and are not protocol defaults or prescribing guidance.
Safety Tips
- Double-check calculations: Always verify the math before you rely on it
- Use consistent syringe size: Stick with the same syringe type to avoid confusion
- Separate math from protocol decisions: A correct unit conversion does not establish a recommended regimen
- Label your vials: Mark concentration and reconstitution date
- Verify clarity: Discard if solution appears cloudy or discolored
Understanding Concentrations
Concentration is how much peptide is dissolved per ml of liquid. Higher concentrations mean less volume per dose, but require more precision. Lower concentrations are easier to measure accurately but require larger volumes to draw.
Example: If you have 10mg of peptide and add 2ml of BAC water:
- Concentration = 10mg ÷ 2ml = 5mg/ml
- On a 100-unit syringe: Each unit = 5 ÷ 100 = 0.05mg (50 mcg)
- For a 0.25mg dose (250 mcg): 0.25 ÷ 0.05 = 5 units
Troubleshooting Common Issues
Dose exceeds syringe capacity?
- • Use a larger syringe (e.g., switch from 30-unit to 100-unit)
- • Reduce reconstitution volume for higher concentration
- • Split the amount across multiple draws
Dose is less than 2 units?
- • Increase reconstitution volume for lower concentration
- • Use a smaller syringe for better precision
- • Very small doses (<1 unit) are difficult to measure accurately
Formulas & Evidence Basis
This calculator uses standard pharmaceutical dilution math:
- Concentration (mg/ml) = Total Peptide (mg) ÷ Reconstitution Volume (ml)
- mg per syringe unit = Concentration (mg/ml) ÷ 100
- Units to draw = Desired Dose (mg) ÷ mg per unit
The ÷ 100 factor derives from the U-100 insulin syringe standard: all three common insulin syringe sizes (30-unit/0.3ml, 50-unit/0.5ml, 100-unit/1.0ml) hold exactly 100 units per ml, so each unit always equals 0.01 ml regardless of syringe size. This is the international standard for insulin syringes per USP requirements.
- • FDA — Insulin Syringe Standard (ISO 8537) — U-100 concentration basis
- • DailyMed: Bacteriostatic Water for Injection — 0.9% benzyl alcohol preservative
- • DailyMed: Sterile Water for Injection — preservative-free, single-dose
- • CDC Injection Safety — multi-dose vial and solvent guidance
Peptide Calculator FAQ
Visible calculator questions supporting the unit-conversion queries this page targets.
How do I convert a peptide dose into syringe units?
First calculate concentration in mg per mL, then convert that concentration into mg per unit on a U-100 insulin syringe. This calculator performs those steps automatically from vial size, reconstitution volume, and target dose.
Does syringe size change the mg-per-unit math?
No. U-100 insulin syringes use the same 100-units-per-mL standard across 30-unit, 50-unit, and 100-unit syringe bodies. Syringe size changes visual range and handling comfort, not the underlying per-unit volume.
What if my target dose is less than 2 units?
Very small doses are harder to measure accurately. The usual fix is to lower concentration by adding more diluent or switch to a syringe that gives better practical readability for the same U-100 standard.
Why does concentration matter more than vial size alone?
Vial size does not determine dose by itself. The practical dose per unit depends on how much peptide is in the vial and how much liquid was added during reconstitution.
Can I use this calculator for tirzepatide, semaglutide, and BPC-157?
Yes. The calculator handles the concentration math for any peptide where you know the total vial amount, the reconstitution volume, and the target dose.
Is bacteriostatic water different from saline or sterile water?
Yes. BAC water includes 0.9% benzyl alcohol as a bacteriostatic preservative, while sterile water has no preservative and saline has sodium chloride instead. Solvent choice changes handling workflow and may change practical stability expectations.
Can I rely on the example rows as dosing instructions?
No. The example rows are calculation examples only. They show how concentration and syringe math work; they are not medical, prescribing, or protocol instructions.
Why does the page emphasize U-100 insulin syringes?
Because they are the most common syringe format used for this style of calculation. Their fixed 0.01 mL per unit standard makes conversion logic consistent and easier to explain.
Comparing two peptides?
The calculator handles the unit math for any compound. If you are deciding between two of them, these side-by-side comparisons cover mechanism, evidence maturity, and how far storage and handling guidance actually extends.