Convert Milligram to Microgram (mg → µg)
The milligram is the standard unit for pharmaceutical dosing, vitamin labeling, and chemistry lab measurements.
Milligram to Microgram Conversion Table
10 common values| Milligram | Microgram |
|---|---|
| 1 mg | 1,000 µg |
| 5 mg | 5,000 µg |
| 10 mg | 10,000 µg |
| 25 mg | 25,000 µg |
| 50 mg | 50,000 µg |
| 100 mg | 100,000 µg |
| 250 mg | 250,000 µg |
| 500 mg | 500,000 µg |
| 1,000 mg | 1,000,000 µg |
| 5,000 mg | 5,000,000 µg |
How to Convert Milligram to Microgram Manually
Step by StepConverting milligrams to micrograms is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.
- 1Take your value in milligramsStart with the number of milligrams (mg) you want to convert.
- 2Multiply by 1,000The conversion factor from mg to µg is 1,000. Multiply your value by this number.
- 3Read the result in microgramsThe result is your value in micrograms (µg).
Formula
Multiply the value in milligrams by 1,000. For the reverse direction, multiply by 0.001.
µg = mg × 1,000mg = µg × 0.001Tips
Use these in everyday conversions- 1 mg = 1/1000 g = 1,000,000 µg. Always check which prefix the label uses.
- Read medication labels carefully — confusing mg and µg can be a 1000× dosing error.
- Nutrition labels list minerals in mg and vitamins (A, D, K) in µg.
Common Mistakes
Avoid these- Reading 500 mg as 500 g on a medicine bottle — a potentially fatal 1000× error.
- Confusing mg (milligram) with mg/kg (dose per kilogram of body weight).
- Mixing up mg and µg — µg is 1000× smaller.
About Milligram and Microgram
What is the Milligram?
The milligram equals one thousandth of a gram (0.001 g) or 10⁻⁶ kilograms, and is the standard unit for pharmaceutical dosing, vitamin labeling, food additives, and chemistry laboratory work. A typical aspirin tablet contains 325–500 mg of active ingredient, and recommended daily vitamin C intake is around 75–90 mg. The milligram is essential in toxicology (LD50 values are often given in mg per kg of body weight), water-quality testing (dissolved minerals in mg/L), and trace-element analysis. It relates to the gram (1,000 mg = 1 g), the microgram (1,000 µg = 1 mg), and the grain (1 grain ≈ 64.8 mg). Pharmaceutical prescriptions worldwide rely on milligrams, and accurate sub-milligram balances are standard in research and pharmacy environments.
- Prescription and over-the-counter drug dosing
- Vitamin and mineral supplement labelling
- Trace element analysis in laboratories
A paracetamol tablet is 500 mg. Daily iron intake: 8 mg (men) / 18 mg (women). Aspirin for heart protection: 75–100 mg daily.
What is the Microgram?
The microgram equals one millionth of a gram (10⁻⁶ g) and is the standard unit for very small mass measurements in pharmacology, environmental science, and trace-element nutrition. The Greek letter µ (mu) represents the SI prefix 'micro' (one millionth). Vitamin B12 daily intake is around 2.4 µg, and the lethal dose of botulinum toxin is in the nanogram-to-microgram range, making it one of the most potent biological substances known. The microgram is critical in air-quality monitoring (PM concentrations in µg/m³), trace-mineral supplements (selenium, iodine), and pharmaceutical compounding. It relates to the milligram (1,000 µg = 1 mg) and the nanogram (1,000 ng = 1 µg). Environmental regulators set legal limits on heavy metals (lead, arsenic) in drinking water in micrograms per liter.
- Vitamin D, A and K dosing
- Trace metal content in food and water
- Hormone replacement therapy dosing
Vitamin D adult dose: 15–20 µg/day. Selenium RDA: 55 µg/day. Many thyroid medications are dosed in µg.