How many micro grams in a gram?

0.001 grams equals 1 milligrams (mg).

And 0.001 milligrams in 1 microgram (mg), therefore 0.000001 grams (or 1 x 10-6) in 1 microgram.

There are therefore 100,000 micrograms in a gram and in context 1000 milligrams in a gram.