it would be nice if the producers of iodine containing compounds would provide the molar concentrations of their solutions rather than the percentages

...remember your high school chemistry that a mole of substance is the molecular mass in grams of that substance, and that a molar (M) solution is that amount dissolved in a liter of water, or that a molal (m) solution is dissolved in a 1000g of solvent (typically other than water)

for potassium iodide (KI).... K, mass of 39, I, mass of 127 so a mole (mol) of KI is 166g per mol... dissolved in a liter of water would be a 1M solution of KI

millimole...so if there are 166g KI per liter.... there are 166mg KI per milliliter (ml)

calibration or standardization of the eyedropper/ml calculations....there are a variety of "standards" when doing calculations...there are typically 20 drops of water per mililiter in normal chem calculations, but approx 15 drops for a solution of KI

to titrate for the recommended adult dosage of KI for thyroid blocking of 130mg per day you need 130/166 of 1 ml or around 12drops on the 15d/ml or about 16 drops if the 20 drops /ml value is used