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For research use only. Not for human or veterinary use. Not a drug, food, or dietary supplement.
Lab math

Peptide molarity calculator

Mass divided by molecular weight gives moles; moles divided by volume gives molarity. Enter the three numbers and watch the flask fill.

These tools do not provide dosing guidance and are not for human or veterinary use. They are for research-use laboratory calculations only. Verify every result independently.

Molarity

Molar concentration from mass, molecular weight, and volume.

Pre-filled from LL-37.

Enter values above to calculate.

molarity (mol/L) = [mass (g) ÷ molecular weight (g/mol)] ÷ volume (L)

Flask fills to the volume you enter

How it works

Many assay protocols specify concentrations in molar units rather than mass units, because a mole counts molecules regardless of how heavy each one is. To convert, you need the molecular weight of the peptide, which Amiravo lists on each compound page from PubChem records.

The calculator converts milligrams to grams, divides by molecular weight to get moles, then divides by the volume in litres. Results are shown in millimolar and micromolar.

Step by step

  1. Convert the mass to grams (mg ÷ 1,000).
  2. Divide by molecular weight (g/mol) to get moles.
  3. Convert the volume to litres (mL ÷ 1,000).
  4. Molarity = moles ÷ litres; multiply by 1,000 for mM.

Frequently asked

Divide the mg/mL value by the molecular weight in g/mol and multiply by 1,000 to get mM. For BPC-157 (1,419.5 g/mol), a 1 mg/mL solution is about 0.70 mM, or 704 µM.