Convert grams to milligrams

Gram (g) to milligram (mg). One gram equals 1000 milligrams.

1 g =1000mg (milligrams)

Formula

milligrams = grams × 1000

Gram to milligram conversion table

GramsMilligramsMilligramsGrams
1 g1000 mg1 mg0.001 g
2 g2000 mg2 mg0.002 g
3 g3000 mg3 mg0.003 g
5 g5000 mg5 mg0.005 g
10 g10000 mg10 mg0.01 g
20 g20000 mg20 mg0.02 g
50 g50000 mg50 mg0.05 g
100 g100000 mg100 mg0.1 g
500 g500000 mg500 mg0.5 g
1000 g1000000 mg1000 mg1 g

To convert grams to milligrams, multiply the number of grams by 1000. One gram equals 1000 milligrams, and one milligram equals 0.001 grams, so the relationship is fixed and exact. As a worked example, 10 g comes to 10000 mg. Enter your own figure in the converter above to get an instant answer, or use the swap button to flip the direction. This is a mass conversion, and like every tool on UnitGlide it runs locally in your browser with no account or upload required. The table further down shows a range of common gram values already worked out in milligrams, plus the reverse milligram to gram direction, which is handy for quick reference or double-checking a result by hand.

Frequently asked questions

How many milligrams are in a gram?

One gram equals 1000 milligrams. The ratio is constant, so you can multiply any number of grams by 1000 to get milligrams.

What is the formula to convert grams to milligrams?

Use milligrams = grams × 1000. UnitGlide applies this exact formula for every value, so results stay accurate across the whole range.

How do I convert milligrams back to grams?

Go the other way by using one milligram equals 0.001 grams. You can also press the swap button in the converter above to flip the direction in one click.

Is this gram to milligram converter accurate?

Yes. It uses internationally defined SI conversion factors, as maintained by the BIPM, and all math runs in your browser so nothing is rounded away on a server. For everyday use the displayed precision is more than enough.

Related conversions

Embed this converter or use the API

Put this converter on your own site, or call the free JSON API. Full documentation is on the developers page.

Embed (iframe)

<iframe src="https://unitglide.net/embed/g-to-mg" width="360" height="200"
        style="border:1px solid #e2e6ec;border-radius:12px"
        title="Gram to Milligram converter"></iframe>
<p><a href="https://unitglide.net/convert/g-to-mg">Gram to Milligram Converter</a> by UnitGlide</p>

API

https://unitglide.net/api/convert?from=g&to=mg&value=1