Free Peptide Dosage Calculator
Free, vendor-neutral peptide dosage and reconstitution calculator. Calculate exact U-100 syringe units, track costs, and visualize pharmacokinetics for 50+ peptides including tirzepatide, semaglutide, retatrutide, and BPC-157.
How It Works
1. Enter Your Vial Info
Select your peptide and enter the vial size (mg) and how much bacteriostatic water you'll add.
2. Set Your Dose
Enter your target dose in mg or mcg. The calculator instantly computes your concentration and draw volume.
3. Draw With Confidence
See exactly how many units to draw on your insulin syringe. Track doses per vial and cost per injection.
Supported Peptides
Our calculator includes dosing data for 50+ peptides across multiple categories, with half-life values and typical dose ranges sourced from FDA prescribing information and peer-reviewed research.
GLP-1 Peptides
Tirzepatide, Semaglutide, Retatrutide
Healing Peptides
BPC-157, TB-500, Thymosin Beta-4
Growth Hormone
CJC-1295, Ipamorelin, Tesamorelin
Longevity & More
Epithalon, MOTS-c, SS-31
Or jump directly to a specific peptide calculator:
Why The Two-Syringe Method Matters
Many peptide users make the mistake of using a single syringe for both reconstitution and injection. This can lead to contamination, inaccurate dosing, and wasted product. The two-syringe method is the gold standard:
Reconstitution Syringe
Use a larger syringe (3mL or 5mL) to add bacteriostatic water to your vial. This syringe only touches sterile water — never your skin.
Injection Syringe
Use a fresh insulin syringe for each injection. U-100 syringes provide precise measurement for peptide doses, typically 5-50 units.
Frequently Asked Questions
How do I reconstitute a peptide vial?
Draw bacteriostatic water (BAC water) into a syringe, then inject it slowly into the peptide vial along the inside wall. Do not shake — gently swirl until the powder dissolves completely. Once reconstituted, store in the refrigerator and use within 4-6 weeks.
What is the difference between mg and mcg?
A milligram (mg) is 1,000 times larger than a microgram (mcg). 1 mg = 1,000 mcg. Our calculator automatically converts between units so you always know exactly how many syringe units to draw.
How do I read an insulin syringe?
U-100 insulin syringes measure in 'units' where 100 units = 1 mL. If your calculation shows 10 units, draw to the 10-unit mark. Most peptide doses fall between 5-50 units on a standard 1mL insulin syringe.
Why does the amount of BAC water matter?
The volume of bacteriostatic water determines your concentration. More water = lower concentration = larger injection volume per dose. Less water = higher concentration = smaller injection volume. Our auto-solve feature finds the optimal amount for clean, easy-to-measure doses.
How long does reconstituted peptide last?
Most reconstituted peptides remain stable for 4-6 weeks when refrigerated at 2-8°C (36-46°F). Never freeze reconstituted peptides. Keep them away from light and always use bacteriostatic water (not sterile water) for longer shelf life.
Is this calculator medically accurate?
Our calculations use standard pharmacological formulas based on FDA prescribing information and peer-reviewed research. However, this tool is for educational purposes only. Always follow your prescribing physician's instructions and never self-administer prescription peptides without medical supervision.