Peptide Reconstitution Calculator

How does the peptide reconstitution calculator work?

Enter three values: (1) the amount of peptide in the vial (e.g. 5 mg semaglutide), (2) the volume of bacteriostatic water you'll add as diluent (e.g. 2 mL), (3) the target research dose per draw (e.g. 0.25 mg). The calculator computes the final concentration (mg/mL), the exact draw volume (mL), and the total number of doses available in the reconstituted vial.

What peptides does this calculator work for?

Any lyophilized research peptide reconstituted with bacteriostatic water — semaglutide, tirzepatide, retatrutide, BPC-157, TB-500, ipamorelin, sermorelin, CJC-1295, MOTS-C, GHK-Cu, and others. The math is concentration-based and applies to any peptide whose vial strength (mg) and target dose are known.

Why use a calculator instead of measuring by eye?

Most research peptide draws are in the 0.05–0.30 mL range. Converting mg dose → mg/mL concentration → mL draw volume is multi-step, error-prone arithmetic. A calculator eliminates the math errors that compromise research dose precision.

Is the calculator accurate enough for research protocols?

The math is exact — concentration = peptide mg ÷ diluent mL, and draw volume = target dose ÷ concentration. The accuracy depends on the input precision (correct vial strength, correctly measured diluent volume, accurate target dose). For research-protocol work, always verify the inputs against the compound's published methods.

What's the standard ratio for most peptides?

Two common standards: 2.5 mg/mL (achieved by adding 2 mL bacteriostatic water to a 5 mg vial) and 5 mg/mL (achieved by adding 2 mL water to a 10 mg vial). Most semaglutide research uses 2.5 mg/mL; most tirzepatide, retatrutide, BPC-157, and TB-500 research uses 5 mg/mL. The calculator works for both and for any custom ratio.