Peptide Reconstitution & Supply Calculator

How the Calculation Works

The math is straightforward once you understand the relationship between mg, mL, and syringe units. Worked example with Tesamorelin (10 mg vial, 1.6 mg standard dose):

1. Concentration = Peptide in vial (mg) ÷ Bac water added (mL)
   10 mg ÷ 2 mL = 5 mg/mL
2. Volume to inject = Desired dose (mg) ÷ Concentration (mg/mL)
   1.6 mg ÷ 5 mg/mL = 0.32 mL
3. Syringe units = Volume (mL) × 100 (for a 100-unit insulin syringe)
   0.32 mL × 100 = 32 units

A standard 1 mL insulin syringe has 100 unit markings. Each unit equals 0.01 mL. So for a 1.6 mg Tesamorelin dose, you draw to the 32-unit mark.

Recommended Reconstitution Volumes

Pick a compound above and we’ll pre-fill the bac water amount that puts the typical dose on a clean, easy-to-read insulin-syringe mark. Common recipes:

• Tesamorelin - 10 mg vial + 2 mL bac water → 5 mg/mL · 1.6 mg dose = 32 IU
• GLP-1 RC-S (semaglutide-style) - 10 mg vial + 2 mL bac water → 5 mg/mL · 2 mg dose = 40 IU
• GLP-1 RC-T (tirzepatide-style) - 10 mg vial + 2 mL bac water → 5 mg/mL · 2.5 mg starting dose = 50 IU (higher maintenance doses need a larger vial or two injections)
• BPC-157 - 5 mg vial + 2.5 mL bac water → 2 mg/mL · 500 mcg dose = 25 IU
• Ipamorelin / CJC-1295 no DAC - 2 mg vial + 2 mL bac water → 1 mg/mL · 200 mcg dose = 20 IU
• PT-141 - 10 mg vial + 2 mL bac water → 5 mg/mL · 1.75 mg dose = 35 IU

Why the Supply Estimate Is Conservative

The “weeks per vial” and “weeks per pack” figures apply a 20% real-world buffer on top of the naïve dose × frequency math. That covers:

• Vial dead-space - a few microlitres of peptide stay behind when you draw from a vial, especially toward the bottom of the bottle.
• Syringe dead-volume - insulin syringes lose ~0.04 mL per draw in the needle hub.
• Draw inaccuracy and the occasional re-draw or spilled dose.

For titration compounds (the GLP-1 family, cagrilintide), the supply estimate also uses the maintenance-phase dose instead of the low starting dose - otherwise a 400 mg supply at the starting 2 mg/week would project out to nearly four years, which doesn’t match how most researchers actually titrate up. The label next to “weeks per vial” flips to maint. + 20% buffer when this applies.

Common Questions

• What if I use a 0.5 mL syringe? - A 50-unit syringe (0.5 mL) has the same unit-to-volume ratio: each unit is still 0.01 mL. The calculator results are the same; you just can’t draw more than 50 units per injection.
• Does it matter how much bac water I add? - More water = lower concentration = more units per dose (larger injection volume). Less water = higher concentration = fewer units per dose. The total mg in the vial stays the same either way. The pre-filled volume above is the one that puts the typical dose at a comfortable, readable IU mark.
• mcg vs mg? - 1 mg = 1,000 mcg (micrograms). Many peptide protocols specify doses in mcg. Just divide by 1,000 to convert to mg, or multiply the mg result by 1,000 to get mcg. The dose tier card has a mcg/mg toggle when you pick Custom.
• Can I turn off the 20% supply buffer? - Not in the UI - it’s baked into the supply estimate on purpose, since over-ordering is much safer than running out mid-protocol. The “injection volume” and “units to draw” numbers are always the exact math, not buffered.