How to convert mg to mcg
Multiply milligrams by 1,000 to get micrograms, and divide micrograms by 1,000 to get milligrams. One milligram is 1,000 micrograms and one gram is 1,000 milligrams.[1]
mcg = mg × 1,000 · mg = mcg ÷ 1,000
mg to mcg chart
| mg | mcg |
|---|---|
| 0.001 mg | 1 mcg |
| 0.01 mg | 10 mcg |
| 0.025 mg | 25 mcg |
| 0.05 mg | 50 mcg |
| 0.1 mg | 100 mcg |
| 0.125 mg | 125 mcg |
| 0.2 mg | 200 mcg |
| 0.25 mg | 250 mcg |
| 0.5 mg | 500 mcg |
| 0.75 mg | 750 mcg |
| 1 mg | 1,000 mcg |
| 1.5 mg | 1,500 mcg |
| 2 mg | 2,000 mcg |
| 2.5 mg | 2,500 mcg |
| 5 mg | 5,000 mcg |
| 10 mg | 10,000 mcg |
mcg to mg chart
| mcg | mg |
|---|---|
| 1 mcg | 0.001 mg |
| 5 mcg | 0.005 mg |
| 10 mcg | 0.01 mg |
| 25 mcg | 0.025 mg |
| 50 mcg | 0.05 mg |
| 100 mcg | 0.1 mg |
| 125 mcg | 0.125 mg |
| 200 mcg | 0.2 mg |
| 250 mcg | 0.25 mg |
| 300 mcg | 0.3 mg |
| 400 mcg | 0.4 mg |
| 500 mcg | 0.5 mg |
| 750 mcg | 0.75 mg |
| 1,000 mcg | 1 mg |
| 2,500 mcg | 2.5 mg |
| 5,000 mcg | 5 mg |
Why mg and mcg mix-ups are dangerous
A mix-up between mg and mcg is a 1,000-fold error, which is why safety groups target it. The Institute for Safe Medication Practices lists “µg” as error-prone because it can be read as “mg”, and recommends writing “mcg”. It also warns against a trailing zero (1.0 mg read as 10 mg) and a missing leading zero (.5 mg read as 5 mg).[2]
- Write “mcg”, never “µg” or “ug”.
- Keep the leading zero: 0.5 mg, not .5 mg.
- Drop trailing zeros: 1 mg, not 1.0 mg.
- Convert before you calculate: a dose in mcg and a strength in mg/mL must be put in the same unit first; mcg to units does it for a syringe.
mcg on supplement labels
US Supplement Facts labels now give vitamin D in mcg, with IU allowed only in parentheses.[3] If a label still shows IU, convert it with the IU to mg converter.
How we checked these numbers
Every result on this page comes from the same code as the calculator, and the known answers below are run as tests before each release.
| Input | Expected | Basis |
|---|---|---|
| 250 mcg → mg | 0.25 | 1 mg = 1,000 mcg |
| 2.5 mg → mcg | 2,500 | 1 mg = 1,000 mcg |
| 0.001 mg → mcg | 1 | 1 mg = 1,000 mcg |
Known limits.
- Converts mass units only. To turn a mass into a volume you also need the concentration; see mg to mL.
Download the data. mg ⇄ mcg chart (CSV)
Change log.
- : Converter and charts published.
Frequently asked questions
How many mcg are in a mg?
1,000. One milligram equals 1,000 micrograms.
What is 500 mcg in mg?
0.5 mg. Divide micrograms by 1,000.
Is mcg the same as µg?
Yes, both mean microgram. Write “mcg”, because “µg” can be misread as “mg”.
Is mcg bigger than mg?
No. A microgram is one thousandth of a milligram, so 1 mg is 1,000 times larger than 1 mcg.