ounce to milligram converter

Convert ounce to milligram in the Mass & weight family. See a sample calculation, unit definitions, and the interactive converter.

Example conversion: 1 oz

28349.52313 milligram

This example is calculated from the same unit registry used by the interactive converter.

Formula and unit definitions

Convert mass and commonly used weight measures across SI, US customary, imperial and scientific systems.

target value = source value × source factor ÷ target factor

Source unit: ounce (oz), factor 0.02834952313, offset 0.

Target unit: milligram (mg), factor 1e-06, offset 0.

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Important note

The calculation is performed locally from the listed unit definitions. Display results are rounded for readability; high-precision and regulated work should use the governing standard and appropriate significant figures.

For high-precision, regulated or safety-critical use, check the underlying standard and its required precision. Historical and approximate units are identified in their names or family descriptions.

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