Peptide calculator — reconstitution and dose in units
Enter the peptide amount in your vial, the bacteriostatic water you add and the dose you want. The calculator returns the concentration, the injection volume and the exact number of units on a U-100 insulin syringe.
Arithmetic only. This tool does not recommend a dose and is not medical advice. Products referenced are research-grade and are not intended to diagnose, treat, cure or prevent any disease.
How the peptide reconstitution maths works
Reconstitution is one division. The vial holds a fixed amount of peptide in milligrams and you decide how much bacteriostatic water to add. Peptide ÷ water gives the concentration in mg per ml — the only number that matters afterwards.
Because doses are usually written in micrograms, convert first: 1 mg = 1000 mcg. Divide the dose in mg by the concentration to get the volume in ml, then multiply by 100 to read it as units on a U-100 insulin syringe.
- Concentration: peptide (mg) ÷ water (ml)
- Injection volume: dose (mg) ÷ concentration
- Units: injection volume (ml) × 100
The most common mistakes are mixing mg with mcg, assuming a U-40 syringe scale on a U-100 syringe, and changing the water volume later without recalculating — the same dose then needs a different number of units.
Our pens come pre-filled — no calculation needed
Synedica retatrutide ships as a ready-to-use pen at a known concentration with fixed dose increments. There is no powder, no bacteriostatic water and no unit maths.