Convert Ounces to Milligrams

Enter the weight in ounces below to get the value converted to milligrams.

Results in Milligrams:

1 oz = 28,349.523125 mg

Do you want to convert milligrams to ounces?

How to Convert Ounces to Milligrams

To convert an ounce measurement to a milligram measurement, multiply the weight by the conversion ratio. One ounce is equal to 28,349.523125 milligrams, so use this simple formula to convert:

milligrams = ounces × 28,349.523125

The weight in milligrams is equal to the ounces multiplied by 28,349.523125.

For example, here's how to convert 5 ounces to milligrams using the formula above.

5 oz = (5 × 28,349.523125) = 141,747.615625 mg

Ounces and milligrams are both units used to measure weight. Keep reading to learn more about each unit of measure.

Ounces

One ounce is a unit of mass/weight equal to 1/16 of a pound. The common ounce should not be confused with the troy ounce, which is equal to 1/12 of a troy pound.^[1]

The ounce is a US customary and imperial unit of weight. Ounces can be abbreviated as oz, for example 1 ounce can be written as 1 oz.

Milligrams

The milligram is the mass equal to 1/1,000 of a gram, or 0.0154 grains.

The milligram, or milligramme, is an SI unit of weight in the metric system. In the metric system, "milli" is the prefix for 10^-3. Milligrams can be abbreviated as mg, for example 1 milligram can be written as 1 mg.

Ounce Measurements and Equivalent Milligram Conversions

Common ounce values converted to the equivalent milligram value
Ounces	Milligrams
1 oz	28,350 mg
2 oz	56,699 mg
3 oz	85,049 mg
4 oz	113,398 mg
5 oz	141,748 mg
6 oz	170,097 mg
7 oz	198,447 mg
8 oz	226,796 mg
9 oz	255,146 mg
10 oz	283,495 mg
11 oz	311,845 mg
12 oz	340,194 mg
13 oz	368,544 mg
14 oz	396,893 mg
15 oz	425,243 mg
16 oz	453,592 mg
17 oz	481,942 mg
18 oz	510,291 mg
19 oz	538,641 mg
20 oz	566,990 mg
21 oz	595,340 mg
22 oz	623,690 mg
23 oz	652,039 mg
24 oz	680,389 mg
25 oz	708,738 mg
26 oz	737,088 mg
27 oz	765,437 mg
28 oz	793,787 mg
29 oz	822,136 mg
30 oz	850,486 mg
31 oz	878,835 mg
32 oz	907,185 mg
33 oz	935,534 mg
34 oz	963,884 mg
35 oz	992,233 mg
36 oz	1,020,583 mg
37 oz	1,048,932 mg
38 oz	1,077,282 mg
39 oz	1,105,631 mg
40 oz	1,133,981 mg