Convert Ounce (oz) to Milligram (mg)
Category: Mass
1 oz = 28349.523125 mg
High-precision rounding: 6 decimals
How to convert ounce (oz) to milligram (mg)
Mass quantifies the amount of matter. The kilogram is defined by Planck’s constant, which anchors mass to fundamental physics. In practice, grams and pounds dominate everyday use—from recipes and parcels to body weight—while tonnes and long tons appear in logistics and industry.
This converter calculates Ounce (oz) to Milligram (mg) values by using the correct conversion rule for the Mass category. For linear units, standardized factors are used. For temperature, the calculator applies the proper formula with offsets.
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Quick conversion table
Handy values for Ounce (oz) to Milligram (mg). Click a value to open that exact result.
Conversion formula
Linear unit conversions use standardized factors; many are exact by definition (e.g., 1 in = 25.4 mm, 1 ft = 0.3048 m).
Common mistakes
- Confusing mass (lb) with force (lbf) in engineering contexts.
- Mixing metric tonnes (t) with short/long tons.
Unit facts
- Ounce (oz): An ounce (avoirdupois) is exactly 28.349523125 g. Note: precious metals use the troy ounce (~31.1035 g).
- Milligram (mg): A milligram is 1/1,000,000 of a kilogram; used in pharma and lab work.
About Ounce (oz)
Ounce (oz)
Equals 1/16 lb; exactly 28.349523125 g. Used for portions, postage, and precious metals (note: troy ounce differs).
History: Medieval trade used multiple ounces; today the avoirdupois ounce dominates in retail while troy ounce survives in bullion markets.
About Milligram (mg)
Milligram (mg)
Equals 1/1,000,000 kg. Used for dosages, trace contaminants, gemstones, and fine powders. Requires calibrated balances for accuracy.
History: Common in analytical chemistry and pharmacology as instrumentation reached sub-milligram readability.