Tool · Units
Unit converter.
Convert between mass units — and see why "international units" (IU) are a different story. Pure measurement, not a dose.
=
The mass units
- 1 gram (g) = 1,000 milligrams (mg)
- 1 milligram (mg) = 1,000 micrograms (mcg / µg)
- 1 microgram (mcg) = 1,000 nanograms (ng)
Why IU isn't here
International units (IU) measure biological activity, not mass, and the IU-to-mg ratio is defined separately for each substance (HGH, insulin, and so on). There is no universal IU↔mg conversion — converting IU from a number you saw online is exactly how people get the math dangerously wrong. Work from the labeled mass, or your specific product's stated IU/mg.
Measurement only — not a dose or a protocol. For reconstitution and syringe units, use the reconstitution calculator.