How many grams are in a milligram?

1 mg = 0.001 g. To convert any amount, multiply by 0.001.

How do you convert milligrams to grams?

Multiply the number of milligrams by 0.001 to get grams. The formula is shown in the "How it's calculated" section above.

Where does the conversion factor come from?

It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.

Unit converter — Mass

Milligrams to grams converter

Convert milligrams (mg) to grams (g). Source-cited conversion factor, exact to the displayed precision.

Results are mathematically exact for the displayed precision. How we calculate.

How it's calculated

Convert milligrams to grams— the formula

Milligrams convert to grams by multiplying by the published conversion factor. The factor below is exact to the precision shown, sourced from the citation under the formula.

g = mg × 0.001

mg = g × 1000

Mass: SI base unit (BIPM). Avoirdupois conversions: 1 lb = 0.45359237 kg (international agreement 1959); 1 oz = 1/16 lb; 1 stone = 14 lb.

Questions

Frequently asked questions

How many grams are in a milligram?
1 mg = 0.001 g. To convert any amount, multiply by 0.001.
How do you convert milligrams to grams?
Multiply the number of milligrams by 0.001 to get grams. The formula is shown in the "How it's calculated" section above.
Where does the conversion factor come from?
It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.