🔬 Formula reference

Sources and Methodology

Every formula used in the Peptide CostCalc suite is documented below, with its source, example calculation, and known limitations. If you find an error, please contact us.

Core Conversion Formulas

mg to mcg Conversion

mcg = mg x 1000

Standard SI metric prefix conversion. 1 milligram equals 1,000 micrograms.

Concentration Formula

Concentration (mg/mL) = Total Peptide Mass (mg) / Reconstitution Volume (mL)

Example: 10 mg peptide dissolved in 2 mL BAC water gives 5 mg/mL. Limitation: Assumes complete dissolution.

Purity Correction

Effective Mass (mg) = Stated Mass (mg) x (Purity % / 100)

Example: 10 mg vial at 98% purity gives 9.8 mg effective peptide.

Syringe and Volume Formulas

Draw Volume

Draw Volume (mL) = Desired Dose (mg) / Concentration (mg/mL)

Example: 0.5 mg dose at 5 mg/mL concentration: draw 0.1 mL.

Insulin Syringe IU Mark (U-100)

IU Mark = Draw Volume (mL) x 100

U-100 syringes: 100 IU = 1 mL. Example: 0.1 mL = pull to the 10 IU mark.

Vial Portions

Portions = (Concentration mg/mL x Volume mL) / Dose (mg)

Pharmacokinetics

Half-Life Decay

Remaining = Initial Amount x (0.5 ^ (Time / Half-Life))

Based on first-order pharmacokinetic decay. Example: 10 mg with a 3-hour half-life after 6 hours: 10 x 0.25 = 2.5 mg remaining. Limitation: Assumes first-order kinetics. Source: Rowland M, Tozer TN. Clinical Pharmacokinetics and Pharmacodynamics. 4th ed. 2010.

Dosing and Scaling

Weight-Based Dosing

Dose (mg) = Dose per kg (mg/kg) x Body Weight (kg)

kg to lb: divide lb by 2.2046.

Allometric Dose Scaling

Human Dose = Animal Dose x (Human Weight / Animal Weight) ^ 0.75

The 0.75 exponent is the standard allometric scaling coefficient (Kleiber’s Law). Source: Reagan-Shaw S et al. FASEB J. 2008;22(3):659-661.

Cycle Planning

Cycle Cost

Total Cost = (Daily Dose mg / Vial Size mg) x Vials x Vial Price

Vial Yield

Days of Supply = (Vial Size mg x Number of Vials) / Daily Dose mg

Body Composition

Body Fat Percentage (US Navy Method)

Male: BF% = 86.010 x log10(abdomen - neck) - 70.041 x log10(height) + 36.76

Female: BF% = 163.205 x log10(waist + hip - neck) - 97.684 x log10(height) - 78.387

Source: Hodgdon JA, Beckett MB. Naval Health Research Center, 1984.

Protein Intake Reference Ranges

1.6-2.2 g/kg for resistance-trained athletes (Phillips and Van Loon, 2011); 2.3-3.1 g/kg during caloric restriction (Helms et al., 2014). Population-average references, not individual recommendations.

Blend Calculators

Component Concentration in a Blend

Component Concentration (mg/mL) = Component Mass (mg) / Total Reconstitution Volume (mL)

Applies to both BPC-157 + TB-500 blend and KLOW blend calculators.

Last reviewed: June 2026. Report corrections via the Contact page.