Fluid Ounces to Milligrams Conversion Calculator
Enter the volume in fluid ounces below to calculate the weight in milligrams.
Result: Milligrams
1 fl oz = 29.57353 g
Do you want to convert milligrams to fluid ounces?
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How to Convert Fluid Ounces to Milligrams
Since fluid ounces are a unit of volume and milligrams are a unit of mass, which are different physical quantities, we need to know one more physical quantity of the ingredient or substance to convert between them. In this case, we need to account for the density of the substance whenever we do a conversion.
Therefore, to convert between fluid ounces and milligrams of an ingredient or substance, we must either multiply or divide by its density, depending on which direction we are performing the conversion.
Fluid Ounces to Milligrams Formula
To convert a measurement in fluid ounces to milligrams, multiply the volume by the density of the ingredient or material. Note that in order for this to work, the density must be in milligrams per fluid ounce (mg/fl oz).
If the density is given in grams per milliliter (g/mL), then first multiply the density by 29,573.53 to convert to mg/fl oz.
For a density given in g/mL, you can use this simple formula to convert:
milligrams = fluid ounces × 29,573.53 × density
Thus, the weight in milligrams is equal to the volume in fluid ounces multiplied by 29,573.53 times the density (in g/mL) of the ingredient, substance, or material.
For example, here's how to convert 5 fluid ounces to milligrams for an ingredient with a density of 0.7 g/mL.
milligrams = 5 fl oz × 29,573.53 × 0.7 g/mL = 103,507.353 mg
How Many Milligrams Are in a Fluid Ounce?
The actual weight of a fluid ounce will vary depending on the material's density. The conversion table below shows how many milligrams of various wet and dry ingredients are in a fluid ounce.
| Volume in Fluid Ounces: | Weight in Milligrams of: | ||||
|---|---|---|---|---|---|
| Water | Milk | Cooking Oil | All Purpose Flour | Granulated Sugar | |
| 0.01 fl oz | 295.74 mg | 304.61 mg | 260.25 mg | 156.44 mg | 250 mg |
| 0.02 fl oz | 591.47 mg | 609.22 mg | 520.49 mg | 312.89 mg | 500 mg |
| 0.03 fl oz | 887.21 mg | 913.82 mg | 780.74 mg | 469.33 mg | 750 mg |
| 0.04 fl oz | 1,183 mg | 1,218 mg | 1,041 mg | 625.78 mg | 1,000 mg |
| 0.05 fl oz | 1,479 mg | 1,523 mg | 1,301 mg | 782.22 mg | 1,250 mg |
| 0.06 fl oz | 1,774 mg | 1,828 mg | 1,561 mg | 938.66 mg | 1,500 mg |
| 0.07 fl oz | 2,070 mg | 2,132 mg | 1,822 mg | 1,095 mg | 1,750 mg |
| 0.08 fl oz | 2,366 mg | 2,437 mg | 2,082 mg | 1,252 mg | 2,000 mg |
| 0.09 fl oz | 2,662 mg | 2,741 mg | 2,342 mg | 1,408 mg | 2,250 mg |
| 0.1 fl oz | 2,957 mg | 3,046 mg | 2,602 mg | 1,564 mg | 2,500 mg |
| 0.11 fl oz | 3,253 mg | 3,351 mg | 2,863 mg | 1,721 mg | 2,750 mg |
| 0.12 fl oz | 3,549 mg | 3,655 mg | 3,123 mg | 1,877 mg | 3,000 mg |
| 0.13 fl oz | 3,845 mg | 3,960 mg | 3,383 mg | 2,034 mg | 3,250 mg |
| 0.14 fl oz | 4,140 mg | 4,265 mg | 3,643 mg | 2,190 mg | 3,500 mg |
| 0.15 fl oz | 4,436 mg | 4,569 mg | 3,904 mg | 2,347 mg | 3,750 mg |
| 0.16 fl oz | 4,732 mg | 4,874 mg | 4,164 mg | 2,503 mg | 4,000 mg |
| 0.17 fl oz | 5,028 mg | 5,178 mg | 4,424 mg | 2,660 mg | 4,250 mg |
| 0.18 fl oz | 5,323 mg | 5,483 mg | 4,684 mg | 2,816 mg | 4,500 mg |
| 0.19 fl oz | 5,619 mg | 5,788 mg | 4,945 mg | 2,972 mg | 4,750 mg |
| 0.2 fl oz | 5,915 mg | 6,092 mg | 5,205 mg | 3,129 mg | 5,000 mg |
When to Convert Fluid Ounces to Milligrams
Fluid ounces and milligrams are both commonly used to measure cooking ingredients.
For cooking applications, most chefs suggest measuring dry ingredients by weight rather than volume to improve accuracy in the measurements.[1] The density of dry ingredients can vary for a variety of reasons, such as compaction and clumping.
The best way to ensure an accurate conversion is to use a scale. When a scale is not available, a calculator like the one above is a good way to estimate the volume to weight conversion.
Another useful application of weight and volume conversions is chemistry. When performing chemical reactions by combining separate chemicals to produce a new chemical, one must know the exact amount of each chemical to add in order to maximize the yield of the reaction.
It is common to mix powdered chemicals with liquid, or aqueous, chemicals, and this is where it becomes very useful to convert between weights and volumes.[2]
Keep reading to learn more about each unit of measure.
What Is a Fluid Ounce?
The US fluid ounce is a unit of volume equal to 1/16 of a pint or 1/8 of a cup. The fluid ounce is sometimes referred to as just an "ounce" but should not be confused with the unit of weight. One fluid ounce is equal to approximately 29.5735 milliliters, but in nutrition labeling, one fluid ounce is rounded to exactly 30 milliliters.[3]
The fluid ounce is a US customary unit of volume. Fluid ounces can be abbreviated as fl oz, and are also sometimes abbreviated as oz fl. For example, 1 fluid ounce can be written as 1 fl oz or 1 oz fl.
Learn more about fluid ounces.
What Is a Milligram?
The milligram is a unit of mass equal to 1/1,000 of a gram, or 0.0154 grains.
The milligram, or milligramme, is an SI unit of mass in the metric system. In the metric system, "milli" is the prefix for thousandths, or 10-3. Milligrams can be abbreviated as mg; for example, 1 milligram can be written as 1 mg.
A milligram is also frequently referred to as a unit of weight. While technically, a milligram is a measure of mass, and weight is actually a measure of force, the two are equivalent as long as we are performing our calculations on Earth.
For example, an object with a mass of 1 milligram weighs 1 milligram on Earth, but only weighs one-sixth of that on the moon, yet still has the same mass.
Learn more about milligrams.
References
- National Institute of Standards & Technology, Culinary Measurement Tips, https://www.nist.gov/pml/owm/culinary-measurement-tips
- CK-12 Foundation, Introductory Chemistry (CK-12) - 12.6: Mass-Volume Stoichiometry, https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry_(CK-12)/12%3A_Stoichiometry/12.06%3A_Mass-Volume_Stoichiometry
- U.S. Food & Drug Administration, Guidance for Industry: Guidelines for Determining Metric Equivalents of Household Measures, https://www.fda.gov/regulatory-information/search-fda-guidance-documents/guidance-industry-guidelines-determining-metric-equivalents-household-measures