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Convert Micrograms to Milligrams

1 microgram is 0.001 mg. One microgram is exactly 0.001 milligrams.

One microgram is 0.001 milligrams. To convert micrograms to milligrams, multiply by 0.001; to go the other way, divide by 0.001 or multiply by 1000. The factor is exact rather than rounded: it follows from NIST Handbook 44. One millionth of a gram.

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Milligrams
0.001 mg
Micrograms × 0.001
value * 0.0010.001 mg

1 microgram in every weight unit

UnitValueExact factor
ounces0.00000003527396195 oz× 0.0000000352739619496
pounds0.000000002204622622 lb× 0.00000000220462262185
stone0.0000000001574730444 st× 0.000000000157473044418
US tons0.000000000001102311311 ton× 0.00000000000110231131092
micrograms (as entered)1 mcg
milligrams0.001 mg× 0.001
grams0.000001 g× 0.000001
kilograms0.000000001 kg× 0.000000001
tonnes0.000000000001 t× 0.000000000001

Factors are entered by hand from NIST Handbook 44 rather than derived from a units library, so the ones that terminate are exact rather than rounded.

How do you convert micrograms to milligrams?

  1. 1.Take the measurement in micrograms.
  2. 2.Multiply by 0.001 — that is how many milligrams fit in one microgram.
  3. 3.To go back the other way, divide by 0.001, or multiply by 1000.

Micrograms to milligrams conversion table

MicrogramsMilligrams
1 mcg0.001 mg
2 mcg0.002 mg
3 mcg0.003 mg
4 mcg0.004 mg
5 mcg0.005 mg
6 mcg0.006 mg
7 mcg0.007 mg
8 mcg0.008 mg
9 mcg0.009 mg
10 mcg0.01 mg
12 mcg0.012 mg
15 mcg0.015 mg
20 mcg0.02 mg
25 mcg0.025 mg
50 mcg0.05 mg
100 mcg0.1 mg

What are micrograms and milligrams?

Microgram (mcg)
One millionth of a gram. Written mcg rather than µg on labels deliberately: the Greek letter is the character most often lost in transcription, and a factor of a thousand in a dose is not a rounding error.
Milligram (mg)
One thousandth of a gram, and exactly 1,000 micrograms. The unit almost every medicine is dosed in.

Source: NIST Handbook 44 — mass and weight

Questions people actually ask

How many milligrams are in a microgram?
0.001. One thousandth of a gram, and exactly 1,000 micrograms. The unit almost every medicine is dosed in.
How do I convert milligrams back to micrograms?
Divide by 0.001, or multiply by 1000 — they are the same operation.

Other weight conversions

Milligrams to micrograms — the same conversion the other way.

Calculators that work in weight