How it works

Six calculators cover the peptide workflow: reconstitution, reverse water volume, GLP-1 scheduling, vial duration, half-life decay, and blend math. Here is the formula behind each one.

01

Reconstitution Calculator

Enter your peptide vial size (mg) and the volume of bacteriostatic water (mL) to calculate the concentration in mg/mL. Then enter your desired dose in micrograms to see exactly how many syringe units to draw.

Formula

Concentration = vial_mg ÷ water_mL
mcg/unit = (vial_mg × 1000) ÷ (water_mL × syringe_units)
units_to_draw = desired_dose_mcg ÷ mcg_per_unit

Example

A 5 mg vial reconstituted with 2 mL BAC water → 2.5 mg/mL concentration. For a 250 mcg dose with a 1.0 mL (100-unit) syringe → 25 mcg/unit → draw 10 units.

02

Reverse Calculator

Work backwards from a target concentration to find the optimal water volume. Enter your vial size and desired concentration, and the calculator tells you how much bacteriostatic water to add.

Formula

water_mL = vial_mg ÷ target_concentration_mg_per_mL

Example

Want 5 mg/mL from a 10 mg vial → add 2 mL BAC water.

03

GLP-1 Dose Scheduler

Generate week-by-week dose escalation schedules for semaglutide, tirzepatide, and retatrutide following published clinical protocols. See the exact syringe units for each escalation step.

Formula

Schedule follows FDA-approved dose escalation:
Semaglutide: 0.25 → 0.5 → 1.0 → 1.7 → 2.4 mg/week
Tirzepatide: 2.5 → 5 → 7.5 → 10 → 12.5 → 15 mg/week

Example

Semaglutide week 5 at 0.5 mg/week from a 5 mg/2 mL vial → 4 units with a 100-unit syringe.

04

Vial Duration Calculator

Calculate how many days a reconstituted vial will last based on your dosing frequency and amount. Also shows cost per dose when you enter the vial price.

Formula

days = (vial_mg × 1000) ÷ (dose_mcg × doses_per_day)
cost_per_dose = vial_price ÷ total_doses

Example

A 5 mg vial at 250 mcg once daily = 20 days. At $30/vial → $1.50 per dose.

05

Half-Life Visualizer

Interactive chart showing exponential decay over 5 half-lives for any peptide. Visualize how plasma concentration drops over time to understand optimal dosing frequency.

Formula

C(t) = C₀ × 0.5^(t ÷ t_half)

Example

BPC-157 with a 4-hour half-life: after 8 hours (2 half-lives), 25% of the original dose remains.

06

Blend / Stack Calculator

Plan reconstitution and draw units when two or more peptides share a syringe or a protocol. Each peptide keeps its own concentration math; the calculator lines up the units so you are not doing it on paper.

Formula

units_i = dose_i_mcg ÷ mcg_per_unit_i
If blended in one vial, total_units follows the shared concentration of that vial.

Example

GLOW or KLOW preset: load the stack, set BAC water, read one draw that hits the rate-limiting peptide dose.

Tips for accurate calculations

  • →Always double-check your vial size - common sizes are 2 mg, 5 mg, and 10 mg.
  • →Use only bacteriostatic water (BAC water) for reconstitution, not sterile water.
  • →Reconstituted vials should be stored at 2-8°C and used within 28 days.
  • →When drawing from the vial, inject the same volume of air first to equalize pressure.
  • →You can use decimals in all input fields for precise calculations.
  • →All calculations run entirely in your browser - nothing is sent to any server.