Convert Milligram (mg) to Ounce (oz) instantly.
About these units
Milligram (mg)
A milligram is one-thousandth of a gram and essential for measuring extremely small masses with precision. Pharmacology relies heavily on milligrams to dose medications safely and consistently—especially potent drugs where differences of a few milligrams can be critical. In chemistry and laboratory science, milligrams are used to weigh reagents, catalysts, micro-samples, and test materials. Environmental science uses milligrams per liter or milligrams per kilogram to describe concentrations of contaminants. Its small size makes the milligram ideal for fields requiring strict quantitative control, and its stability within the metric system ensures predictable conversions during calculations.
Ounce (oz)
The ounce is a unit equal to 1/16 of a pound, or approximately 28.3495 grams, with roots in ancient Roman "uncia"—one-twelfth of a pound. The ounce is used for measuring small masses in cooking, postal services, gemstones (troy ounces), and various consumer goods. Despite not being part of the metric system, the ounce remains a staple in US everyday life, from food packaging to hardware components. Its small size gives it a practical niche where grams might feel too unfamiliar for some audiences. Multiple ounce variants exist historically—avoirdupois, troy, apothecary—but the avoirdupois ounce is now the standard in general commerce. Its endurance reflects the cultural weight of imperial units and the long history of Western measurement systems.