Peptide reconstitution calculator
How do I use this?
Calculate exact syringe units, BAC water volume, and concentration for any peptide. Supports Semaglutide, Tirzepatide, BPC-157, Retatrutide, CJC-1295, Ipamorelin, and 70+ compounds. Free, no signup, works offline.
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Peptide guides
Citations to peer-reviewed work where it exists. Community survey data labeled where it doesn't.
Phase 3 trials
Retatrutide
Triple agonist activating GLP-1, GIP, and glucagon receptors. Phase 3 trial data has shown weight reduction averaging up to 24% over 48 weeks.
Read the guide →
FDA-approved
Tirzepatide
Dual GIP/GLP-1 receptor agonist sold as Mounjaro and Zepbound. The 1 mL : 10 mg compounding ratio yields a clean 25-units-per-2.5mg relationship at every titration step.
Read the guide →
Community-documented
BPC-157
A 15-amino-acid peptide derived from human gastric juice. Studied for tendon, ligament, and tissue repair; one 2025 HSS Journal systematic review summarizes the orthopaedic literature.
Read the guide →
Community-documented
CJC-1295
Long-acting GHRH analogue, commonly stacked with Ipamorelin. The DAC variant (Drug Affinity Complex) extends half-life to several days, enabling less frequent dosing.
Read the guide →
All peptide guides
Semaglutide · Tirzepatide · Retatrutide · BPC-157 · TB-500 · CJC-1295 · Ipamorelin · Tesamorelin · Sermorelin · GHK-Cu · Epitalon · PT-141 · Selank · NAD+
Reconstitution & injection reference
The general how-to: reconstitution, syringe math, injection technique, and dosing notes for the most common research peptides. For a specific compound, jump to its full guide above.
Reconstitution basics
How do I reconstitute a peptide?
Add bacteriostatic (BAC) water slowly down the inside wall of your vial containing lyophilized (freeze-dried) peptide. Swirl gently to dissolve. Never shake, as agitation can denature the peptide. The volume of BAC water you add sets the concentration (mg/mL), which sets how many syringe units equal your target dose. Store reconstituted peptides refrigerated at 2-8°C (36-46°F) and use within 4-6 weeks.
How much BAC water should I add?
It depends on your vial size and desired dose. Less water = higher concentration (fewer units per dose). More water = lower concentration (more units, easier to measure on the syringe). The sweet spot is a draw between 10-50 units, where insulin syringes are most precise. For a 5mg vial with a 0.25mg dose, 1-2 mL of BAC water typically produces a convenient 10-20 unit draw.
What is bacteriostatic water?
BAC water is sterile water containing 0.9% benzyl alcohol, which inhibits bacterial growth. It keeps reconstituted peptides stable for 4-6 weeks when refrigerated. Plain sterile water should be discarded within 24 hours. Always use BAC water (not saline or plain sterile water) because the preservative prevents contamination from repeated needle punctures into the same vial.
What is a Certificate of Analysis (COA)?
A COA is an independent lab report showing the actual tested amount of peptide in your vial, which often differs from the label. A vial labeled "10 mg" may contain 9.2 mg or 10.8 mg. Using the COA-verified amount instead of the label amount ensures your dosing math is accurate. Always request a COA from your supplier and enter that amount in DrawDose.
Syringes and measurement
How do I convert peptide mg to syringe units?
On a U-100 insulin syringe, 100 units = 1 mL = 1 cc. To find your draw: divide vial amount (mg) by BAC water volume (mL) to get concentration. Then divide your dose by that concentration to get volume in mL. Multiply by 100 for syringe units. Example: 10mg vial + 2mL BAC water = 5 mg/mL. For a 0.25mg dose: 0.25 ÷ 5 = 0.05 mL = 5 units.
What syringe size should I use?
Peptide injections use U-100 insulin syringes in three sizes: 0.3 mL (30 units), 0.5 mL (50 units), or 1 mL (100 units). Smaller syringes are more precise for small doses. Pick the smallest syringe that fits your calculated draw volume. FDA: Needles and Syringes
Injection technique
SubQ vs IM — where do I inject?
Most peptides are injected subcutaneously (SubQ) into fat tissue: abdomen (at least 2 inches from navel), outer thigh, or back of the upper arm, at a 45-90° angle. Intramuscular (IM) injections go into muscle: deltoid (up to 2 mL), vastus lateralis (outer thigh), or ventrogluteal (hip) at 90°. Ask your healthcare provider which method fits your compound.
Why should I rotate injection sites?
Injecting the same spot repeatedly causes lipohypertrophy (fat buildup) or lipoatrophy (fat loss), which leads to scar tissue and erratic absorption. Nearly half of insulin users develop lipohypertrophy from poor rotation. A practical method: divide each injection area into four quadrants, use one quadrant per week moving clockwise, keep each injection at least 1 inch (2.5 cm) from the last, and wait 7-14 days before returning to the same spot.
Sources: CDC Vaccine Administration, WHO Best Practices for Injections, PMC Lipohypertrophy Research
Common peptides
Semaglutide
Semaglutide is a GLP-1 receptor agonist prescribed for weight management and blood sugar control. Typical titration: 0.25 mg once weekly for 4 weeks, then 0.5 mg, 1 mg, and up to 2.4 mg based on tolerance. Injected SubQ, usually in the abdomen or thigh.
Read the full Semaglutide guide →
Tirzepatide
Tirzepatide targets both GIP and GLP-1 receptors. The titration starts at 2.5 mg weekly for 4 weeks, then steps up through 5 mg, 7.5 mg, 10 mg, 12.5 mg, to a maximum of 15 mg. Injected SubQ. Each titration step changes the syringe draw, so recalculating after each increase matters.
Read the full Tirzepatide guide →
Retatrutide
Retatrutide targets three receptors at once: GIP, GLP-1, and glucagon. Still in clinical trials, Phase 2 data showed up to 24% body weight reduction over 48 weeks. Injected SubQ with a titration protocol starting at lower doses.
BPC-157
Body Protection Compound-157 is a 15-amino-acid peptide studied for tissue repair. Research doses are typically 200-500 mcg per day, injected SubQ near the area of concern. Also available as BPC-157 Arginate (the arginine salt form). Often paired with TB-500 in blend protocols.
Read the full BPC-157 guide →
TB-500 (Thymosin Beta-4)
TB-500 plays a role in cell migration and tissue repair. Research dosing is usually 2-5 mg twice weekly during a loading phase, dropping to 2-5 mg every 1-2 weeks for maintenance. Frequently combined with BPC-157 in a single blend vial.
CJC-1295 and Ipamorelin
This is one of the most common growth hormone secretagogue stacks. CJC-1295 (with or without DAC) stimulates GHRH, and Ipamorelin is a selective ghrelin receptor agonist. Research doses: 100-300 mcg each, often combined in a single injection before bed. Available with or without DAC (Drug Affinity Complex), which extends the half-life.
Read the full CJC-1295 guide →
Other supported peptides
Beyond the compounds above, DrawDose covers 70+ peptides: GLP-1 compounds (Liraglutide, Survodutide, AOD-9604), healing peptides (KPV, LL-37, Larazotide), GH secretagogues (GHRP-2, GHRP-6, Tesamorelin, Sermorelin, Hexarelin), cognitive peptides (Selank, Semax, Dihexa), and anti-aging compounds (Epitalon, GHK-Cu, MOTS-c, NAD+). Each has pre-filled starting doses and protocol references.
DrawDose is not medical advice. All information is for research and educational purposes only. Always consult a qualified healthcare provider before making decisions about peptide use. For clinical drug information, consult the FDA drug database or speak with a licensed pharmacist.
DrawDose publishes technical reference material for research and educational purposes only. Not medical advice. See full disclaimer. Editorial standards · Where to access peptides · Cheat sheet · Privacy · © 2026 Agensum LLC