Milligram (mg)
The milligram (mg) is one thousandth of a gram. It is the standard unit for medicine doses and supplement labels.
Symbol: mg
Quantity: mass (commonly called weight)
SI relation: 1 mg = 0.000001 kg (exact)
Derivation: 1 mg = 10⁻⁶ kg = 10⁻³ g
Exact: yes, by definition
Typical uses
- Medication doses (e.g. 500 mg tablets)
- Nutrition labels (sodium, caffeine)
- Analytical chemistry
Convert milligrams to other units
| Conversion | 1 mg equals | Reverse |
|---|---|---|
| milligram to kilogram | 0.000001 kg | kilogram to milligram |
| milligram to gram | 0.001 g | gram to milligram |
| milligram to pound | 0.000002204622622 lb | pound to milligram |
| milligram to ounce | 0.00003527396195 oz | ounce to milligram |
| milligram to microgram | 1000 µg | microgram to milligram |
| milligram to metric ton | 1 × 10⁻⁹ t | metric ton to milligram |
| milligram to stone | 1.574730444 × 10⁻⁷ st | stone to milligram |
| milligram to short ton | 1.102311311 × 10⁻⁹ ton (US) | short ton to milligram |
| milligram to troy ounce | 0.00003215074657 oz t | troy ounce to milligram |
| milligram to long ton | 9.842065276 × 10⁻¹⁰ ton (UK) | long ton to milligram |
| milligram to grain | 0.01543235835 gr | grain to milligram |
| milligram to carat | 0.005 ct | carat to milligram |
Open the Weight and Mass Converter to convert any value between all units.
Sources
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 7, SI prefixes.
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Milligram (mg). Retrieved October 17, 2026, from https://scientificconverters.com/units/milligram/
IEEE
Scientific Converters, "Milligram (mg)," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/units/milligram/