Convert grams to milligrams
mg = g × 1000. 0.25 g = 250 mg.
mg = g × 1000 — 1 g is 1000 mg
Common values, converted exactly
| grams (g) | milligrams (mg) |
|---|---|
| 0.001 g | 1 mg |
| 0.005 g | 5 mg |
| 0.01 g | 10 mg |
| 0.05 g | 50 mg |
| 0.1 g | 100 mg |
| 0.25 g | 250 mg |
| 0.5 g | 500 mg |
| 1 g | 1000 mg |
| 2 g | 2000 mg |
| 5 g | 5000 mg |
| 10 g | 10000 mg |
Related conversions
To convert grams to milligrams, apply mg = g × 1000. For example, 0.25 g = 250 mg, and 1 g is 1000 mg.
A milligram is exactly one thousandth of a gram: both are metric, so this is a shift of the decimal point, not a measured factor. Doses and supplements are labelled in milligrams. A microgram (mcg or µg) is a thousand times smaller again, and mixing the two up is a thousandfold error.
Everything on this page is computed in your browser from the exact definitions above — the table is not a stored list of pre-rounded answers, and neither is the converter. For a unit not covered here, the full unit converter handles length, weight, volume, temperature and cooking measures.
How many milligrams is 0.25 g?
0.25 g = 250 mg. mg = g × 1000, so any amount converts the same way — the table on this page lists the values most often looked up.
What is the formula for converting grams to milligrams?
mg = g × 1000. A milligram is exactly one thousandth of a gram: both are metric, so this is a shift of the decimal point, not a measured factor. Doses and supplements are labelled in milligrams. A microgram (mcg or µg) is a thousand times smaller again, and mixing the two up is a thousandfold error.
Is the grams to milligrams conversion exact?
The underlying relationship is an exact definition, not a measurement. The decimal factor shown (1000 mg) is a rounding of it, so results here are given to six significant figures — enough for any practical use, and you can see the exact definition above.
How do I convert milligrams back to grams?
Use the reverse of the same relationship; the mg to g page has its own table and converter.