PepExact

mg to mcg converter

One milligram is exactly 1,000 micrograms. This is the conversion behind most dosing arithmetic — and most dosing mistakes.

1 mg = 1,000 mcg. Type in either box — the other updates.

Quick reference

Milligrams (mg)Micrograms (mcg)
0.1 mg100 mcg
0.25 mg250 mcg
0.5 mg500 mcg
1 mg1,000 mcg
2 mg2,000 mcg
2.5 mg2,500 mcg
5 mg5,000 mcg
10 mg10,000 mcg

Vial labels are usually printed in mg; doses are often quoted in mcg. Mixing the two up shifts a number by a factor of 1,000 — the classic "10× or 1,000× error." When in doubt, convert everything to mcg before doing any other arithmetic. Read the full mg vs mcg guide.