Convert Milligrams to Micrograms
1 milligram (mg) equals 1000 micrograms (µg).
1 mg = 1000 µg
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk milligram to microgram converter to paste a column from Excel.
How to Convert Milligram to Microgram
- 1 mg = 1000 µg
- 1 µg = 0.001 mg
- Example: convert 15 mg to µg: 15 mg = 15 × 1000 µg = 15000 µg
Formula
µg = mg × 1000
Derivation from SI units:
- 1 mg = 10⁻⁶ kg = 10⁻³ g
- 1 µg = 10⁻⁹ kg = 10⁻³ mg
- 1 mg = 0.000001 kg ÷ 1 × 10⁻⁹ kg per µg = 1000 µg
Both units are defined exactly, so the factor is exact. Milligram definition: milligram; Microgram definition: microgram.
Worked examples
- A 0.5 mg dose is 500 µg.
0.5 mg × 1000 = 500 µg - 1 mg is 1000 µg.
1 mg × 1000 = 1000 µg
Milligram to Microgram conversion table
| Milligrams (mg) | Micrograms (µg) |
|---|---|
| 0.1 mg | 100 µg |
| 0.5 mg | 500 µg |
| 1 mg | 1000 µg |
| 2 mg | 2000 µg |
| 5 mg | 5000 µg |
| 10 mg | 10000 µg |
| 20 mg | 20000 µg |
| 25 mg | 25000 µg |
| 50 mg | 50000 µg |
| 65 mg | 65000 µg |
| 81 mg | 81000 µg |
| 100 mg | 100000 µg |
| 200 mg | 200000 µg |
| 250 mg | 250000 µg |
| 325 mg | 325000 µg |
| 400 mg | 400000 µg |
| 500 mg | 500000 µg |
| 1000 mg | 1000000 µg |
| 2000 mg | 2000000 µg |
| 5000 mg | 5000000 µg |
Where it's used
Milligram values are converted to micrograms for trace nutrients, potent drugs and environmental limits. Multiply by 1000.
Milligram to other weight and mass units
| Conversion | 1 mg equals |
|---|---|
| milligram to kilogram | 0.000001 kg |
| milligram to gram | 0.001 g |
| milligram to microgram | 1000 µg |
| milligram to metric ton | 1 × 10⁻⁹ t |
| milligram to pound | 0.000002204622622 lb |
| milligram to ounce | 0.00003527396195 oz |
| milligram to stone | 1.574730444 × 10⁻⁷ st |
| milligram to short ton | 1.102311311 × 10⁻⁹ ton (US) |
| milligram to long ton | 9.842065276 × 10⁻¹⁰ ton (UK) |
| milligram to grain | 0.01543235835 gr |
| milligram to troy ounce | 0.00003215074657 oz t |
| milligram to carat | 0.005 ct |
Frequently asked questions
How many micrograms are in a milligram?
Exactly 1000.
How many micrograms are in 1 milligram?
1 mg = 1000 µg.
How do I convert milligrams to micrograms?
Multiply the value in mg by 1000. For example, 15 mg × 1000 = 15000 µg.
Is the mg to µg conversion exact?
Yes. Both units are defined exactly, and 1 mg is exactly 1000 µg.
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). Convert Milligrams to Micrograms. Retrieved October 17, 2026, from https://scientificconverters.com/mass/milligrams-to-micrograms/
IEEE
Scientific Converters, "Convert Milligrams to Micrograms," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/mass/milligrams-to-micrograms/