Grams to milligrams
1 gram = 1,000 milligrams
Type a value in grams (g) to get milligrams (mg) straight away. A gram is larger than a milligram, so the number goes up. Both units belong to weight, measured here against the kilogram.
1 g = 1,000 mg
Formula
mg = g × 1,000
One gram is 1,000 milligrams, so multiply the gram value by that factor. Here g is the value in grams and mg is the result in milligrams.
Worked example: 250 grams × 1,000 = 250,000 milligrams.
Grams to milligrams table
| grams (g) | milligrams (mg) |
|---|---|
| 1 g | 1,000 mg |
| 2 g | 2,000 mg |
| 3 g | 3,000 mg |
| 4 g | 4,000 mg |
| 5 g | 5,000 mg |
| 6 g | 6,000 mg |
| 7 g | 7,000 mg |
| 8 g | 8,000 mg |
| 9 g | 9,000 mg |
| 10 g | 10,000 mg |
| 15 g | 15,000 mg |
| 20 g | 20,000 mg |
| 25 g | 25,000 mg |
| 30 g | 30,000 mg |
| 40 g | 40,000 mg |
| 50 g | 50,000 mg |
| 60 g | 60,000 mg |
| 75 g | 75,000 mg |
| 100 g | 100,000 mg |
Everyday grams in milligrams
| What it is | g | mg |
|---|---|---|
| a paper clip (about) | 1 g | 1,000 mg |
| a teaspoon of sugar (about) | 5 g | 5,000 mg |
| about one ounce | 28 g | 28,000 mg |
| the per-100 g line on food labels | 100 g | 100,000 mg |
| about one pound | 454 g | 454,000 mg |
Quick estimate in your head
Multiply by 10^3: move the decimal point 3 places right (add 3 zeros).
About the units
Gram (g). One thousandth of a kilogram. Used for food, post and jewellery.
Milligram (mg). One thousandth of a gram. Used for medicine doses and nutrition labels.
Going the other way, 1 milligram is 0.001 grams.
Questions
How many milligrams are in 1 gram?
1 gram is 1,000 milligrams, and 1 milligram is 0.001 grams.
How do I convert grams to milligrams?
Use mg = g × 1,000. For example, 250 grams × 1,000 = 250,000 milligrams.
Is the gram to milligram factor exact?
The factor comes from the unit definitions. Results here are rounded to 6 significant digits for display.
How much is about one pound in milligrams?
454 g is 454,000 mg.
Source for the conversion factor: NIST SP 811, Appendix B (conversion factors).