Milligrams (mg) to Micrograms (μg) Converter
Enter a value to instantly convert between weight units.
1 Milligram = 1000 Microgram
Key Formulas
Kilogram → Pound
lb = kg × 2.20462Pound → Kilogram
kg = lb × 0.453592Gram → Ounce
oz = g × 0.035274Ounce → Gram
g = oz × 28.3495Formula
μg = mg × 1000A microgram is one-thousandth of a milligram — a ratio of 1000-to-1, the same as meters to millimeters. Pharmaceutical compounds, clinical measurements, and trace environmental analysis often work at the microgram level, so converting from mg to μg means multiplying by 1000. This is fundamental in pharmacology, toxicology, and any lab that measures trace substances.
Source: NIST SP 811, Table B.8
Frequently Asked Questions
Real-World Examples
A pharmacist preparing a 1 mg/ml solution knows that 1 ml contains 1000 μg of active compound.
1 mg = 1000 μg
A clinical lab reporting 0.5 mg of a hormone per liter needs to express it as 500 μg/L for the medical record.
0.5 mg = 500 μg
A nutritional supplement containing 5 mg of vitamin B12 per tablet is 5000 μg for the label.
5 mg = 5000 μg
A water quality test finding 0.01 mg/L of a contaminant reports 10 μg/L to the EPA.
0.01 mg = 10 μg