How this calculator works
Use this mode when your target amount is already expressed in micrograms. Enter the vial mass and final liquid volume to calculate mcg/mL, then enter your own target. One mg equals 1,000 mcg; check the unit label rather than comparing bare numbers.
Formula
Target volume = target mcg ÷ concentration in mcg/mL. U-100 marking = target volume × 100.
Arithmetic example — not a recommendation
Arithmetic example only: 2 mg in 1 mL gives 2,000 mcg/mL. A user-entered target of 100 mcg corresponds to 0.05 mL, or 5 U-100 units.
Scope and assumptions
There is no universal mcg-to-units conversion. Tiny computed values can exceed the precision of real equipment; displayed decimals do not certify measurability.
Mass is normalized to mcg; volume stays in mL. Where shown, U-100 means 100 scale units per mL. Read all formulas and precision rules.