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Single conversion
To convert from Milligram (mg) to Microgram (mcg), use the following formula:
Let's convert 5 Milligram (mg) to Microgram (mcg).
Using the formula:
Therefore, 5 Milligram (mg) is equal to Microgram (mcg).
Here are some quick reference conversions from Milligram (mg) to Microgram (mcg):
| Milligrams | Micrograms |
|---|---|
| 0.000001 mg | mcg |
| 0.001 mg | mcg |
| 0.1 mg | mcg |
| 1 mg | mcg |
| 2 mg | mcg |
| 3 mg | mcg |
| 4 mg | mcg |
| 5 mg | mcg |
| 6 mg | mcg |
| 7 mg | mcg |
| 8 mg | mcg |
| 9 mg | mcg |
| 10 mg | mcg |
| 20 mg | mcg |
| 30 mg | mcg |
| 40 mg | mcg |
| 50 mg | mcg |
| 100 mg | mcg |
| 1000 mg | mcg |
| 10000 mg | mcg |
For all Weight converters, choose units using the From/To dropdowns above.
A milligram, abbreviated as mg, is a tiny unit of mass in the metric system.
It's equal to one-thousandth of a gram (0.001 g). While incredibly small, the milligram plays a massive role in our daily health, from the medicine we take to the food we eat.
The milligram (mg) is a critical unit of measurement for quantifying the active ingredients in medications. Its small size allows for the precise dosage needed to make a drug effective and safe.
Why is dosage in mg so important?
You'll see milligram (mg) dosages clearly listed on standard medications, such as aspirin, ibuprofen, and prescription pills.
When you read a nutrition facts label, you'll see many vitamins and minerals listed in milligrams (mg).
Essential nutrients like Vitamin C, iron, calcium, and sodium are all measured in mg to help you understand your daily intake. For example, the recommended daily allowance of Vitamin C for an adult is around 75-90 mg. Understanding these measurements is key to maintaining a balanced and healthy diet.
It can be difficult to picture just how small a milligram is. Here's a simple way to visualize it:
The name itself gives a clue: it combines the Latin prefix "milli" (meaning "thousandth") with the base unit, gram. This means there are 1,000 milligrams in one gram.
A microgram (mcg) is a unit of mass equal to one-millionth of a gram.
While the official symbol for the microgram in the International System of Units (SI) is μg (using the Greek letter Mu), you'll often see it written as mcg.
This is particularly common in the medical and pharmaceutical fields.
Using 'mcg' is a crucial safety measure to prevent dosage errors. A handwritten 'μg' could easily be mistaken for 'mg' (milligram), which would result in a 1,000-times overdose—a potentially fatal mistake.
The microgram is the go-to unit for measuring very potent substances, where tiny differences matter for both safety and effectiveness.
It's used for specific substances like:
Measuring in micrograms makes it possible to give an effective dose without risking toxicity.
It's hard to picture how tiny a microgram is.
For perspective, a single grain of ordinary table salt weighs about 500–600 micrograms — meaning a single grain contains more than 500 micrograms.
That helps explain why we measure very potent substances in micrograms: their active doses are tiny.