Grams to Milligrams Converter
Convert grams to milligrams instantly. 1 g = 1,000 mg. Free two-way converter with the formula and a quick reference table.
How to convert grams to milligrams
milligrams = grams × 1,000
One gram equals 1,000 milligrams, so to convert grams to milligrams you multiply by 1,000. Going the other way, one milligram is 1.0000e-3 grams. Both units measure weight & mass, so the conversion is an exact ratio that never changes.
10 grams = 10,000 milligrams. Multiply your gram figure by the factor above (or just type it into the box) to convert any amount.
Need the other direction? milligrams to grams
grams to milligrams table
| grams (g) | milligrams (mg) |
|---|---|
| 1 | 1,000 |
| 2 | 2,000 |
| 3 | 3,000 |
| 5 | 5,000 |
| 10 | 10,000 |
| 20 | 20,000 |
| 25 | 25,000 |
| 50 | 50,000 |
| 100 | 100,000 |
| 250 | 250,000 |
| 500 | 500,000 |
| 1,000 | 1,000,000 |
Frequently asked questions
How many milligrams are in a gram?
One gram equals 1,000 milligrams. So to convert, multiply the number of grams by 1,000.
How do I convert grams to milligrams?
Multiply by 1,000, or simply enter the value in the converter above — it does the math instantly and works both ways.
Is this conversion exact?
Yes — both units measure the same quantity, so the ratio is fixed and this uses the standard internationally-agreed factor.