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US Fluid Ounces to Milligrams Converter

Convert US fluid ounces (fl oz) to milligrams (mg), with the formula, a conversion table and exact factors.

Change the values and press Calculate to work out your own figures.

Convert cups and spoons to grams or ounces (or back) for a chosen ingredient, using USDA weights, or enter your own density.

The quantity to convert. Fractions such as 3/4 or 1 1/2 are accepted.
Unit you want. Swap exchanges the two units.
Weight per cup differs by ingredient and by how it is measured (sifted, packed, chopped). Each option names the assumption used; choose Other to enter your own density.
Only used when the ingredient is Other: the weight per volume of your ingredient.
Result
Converted amount
29,573.5 mg
Density used
1 g/mL (USDA FDC 174158, 1 ml = 1 g)
Exact
29,573.5295625

1 US fluid ounces of water = 29,573.5 milligrams. Weights for cups and spoons vary with how the ingredient is measured, so treat this as a close estimate.

The same amount in other weight units
UnitAmount
grams29.5735
kilograms0.0295735
ounces (avoirdupois)1.04318
pounds0.0651985
Show the working
  1. 1 fl oz = 29.5735295625 mL
  2. × 1 g/mL (USDA FDC 174158, 1 ml = 1 g) = 29.5735295625 g
  3. = 29573.5295625 mg

How to convert us fluid ounces to milligrams

1 fl oz = 29,573.5 mg, so multiply by 29,573.5 to go from US fluid ounces to milligrams. Going the other way, 1 mg = 0.000033814 fl oz.

mg = fl oz × 29,573.5
fl oz = mg × 0.000033814

Worked example:

5 fl oz = 147.867647812 mL
× 1 g/mL (USDA FDC 174158, 1 ml = 1 g) = 147.867647812 g
= 147867.647812 mg

US Fluid Ounces to milligrams table

US Fluid OuncesMilligrams
1 fl oz29,573.5 mg
2 fl oz59,147.1 mg
3 fl oz88,720.6 mg
4 fl oz118,294 mg
5 fl oz147,868 mg
6 fl oz177,441 mg
7 fl oz207,015 mg
8 fl oz236,588 mg
9 fl oz266,162 mg
10 fl oz295,735 mg
15 fl oz443,603 mg
20 fl oz591,471 mg
25 fl oz739,338 mg
30 fl oz887,206 mg
40 fl oz1,182,940 mg
50 fl oz1,478,680 mg
75 fl oz2,218,010 mg
100 fl oz2,957,350 mg
250 fl oz7,393,380 mg
500 fl oz14,786,800 mg
1000 fl oz29,573,500 mg

About the units

US Fluid Ounces (fl oz)
US fluid ounces, a US customary unit. Definition: NIST Handbook 44 Appendix C (US customary units; US gallon = 231 in³).
Milligrams (mg)
Milligrams, a metric unit. Definition: BIPM SI Brochure.

Formula version 0.1.0Reviewed