Convert Milligrams to Carats
1 milligram is 0.01 ct. One milligram is exactly 0.005 carats.
One milligram is 0.005 carats. To convert milligrams to carats, multiply by 0.005; to go the other way, divide by 0.005 or multiply by 200. The factor is exact rather than rounded: it follows from NIST Handbook 44. One thousandth of a gram, and exactly 1,000 micrograms.
Factor checked against the defining standard · How we check
- Milligrams × 0.005
1 * 0.0050.005 ct
1 milligram in every weight unit
| Unit | Value | Exact factor |
|---|---|---|
| ounces | 0.00003527396195 oz | × 0.0000352739619496 |
| pounds | 0.000002204622622 lb | × 0.00000220462262185 |
| stone | 0.0000001574730444 st | × 0.000000157473044418 |
| US tons | 0.000000001102311311 ton | × 0.00000000110231131092 |
| micrograms | 1,000 mcg | × 1,000 |
| milligrams (as entered) | 1 mg | — |
| centigrams | 0.1 cg | × 0.1 |
| grams | 0.001 g | × 0.001 |
| kilograms | 0.000001 kg | × 0.000001 |
| slugs | 0.00000006852176586 slug | × 0.0000000685217658568 |
| tonnes | 0.000000001 t | × 0.000000001 |
| carats | 0.005 ct | × 0.005 |
| troy ounces | 0.00003215074657 ozt | × 0.0000321507465686 |
| grains | 0.01543235835 gr | × 0.0154323583529 |
| long tons | 0.0000000009842065276 LT | × 0.000000000984206527611 |
Factors are entered by hand from NIST Handbook 44 rather than derived from a units library, so the ones that terminate are exact rather than rounded.
How do you convert milligrams to carats? The converter and the working
- 1.Take the measurement in milligrams.
- 2.Multiply by 0.005 — that is how many carats fit in one milligram.
- 3.To go back the other way, divide by 0.005, or multiply by 200.
Worked example: 25 milligrams to carats
- Formula
- mg × 0.005 = ct
- Arithmetic
- 25 × 0.005 = 0.13 ct
- Answer
- 25 mg = 0.13 ct
The factor is exact, so this figure is exact too — only the display is rounded.
Milligrams to carats conversion table
| Milligrams | Carats |
|---|---|
| 1 mg | 0.01 ct |
| 2 mg | 0.01 ct |
| 3 mg | 0.02 ct |
| 4 mg | 0.02 ct |
| 5 mg | 0.03 ct |
| 6 mg | 0.03 ct |
| 7 mg | 0.04 ct |
| 8 mg | 0.04 ct |
| 9 mg | 0.05 ct |
| 10 mg | 0.05 ct |
| 12 mg | 0.06 ct |
| 15 mg | 0.08 ct |
| 20 mg | 0.1 ct |
| 25 mg | 0.13 ct |
| 50 mg | 0.25 ct |
| 100 mg | 0.5 ct |
| 200 mg | 1 ct |
| 300 mg | 1.5 ct |
| 500 mg | 2.5 ct |
| 1000 mg | 5 ct |
| 2000 mg | 10 ct |
| 5000 mg | 25 ct |
| 10000 mg | 50 ct |
What is a milligram?
One thousandth of a gram, and exactly 1,000 micrograms. The unit almost every medicine is dosed in.
What is a carat?
Exactly 200 milligrams, fixed by international agreement in 1907 after centuries of local carats. It weighs a gemstone; the karat that grades gold is a different word for a different thing — purity in twenty-fourths.
How many carats are in a milligram?
One milligram is 0.005 carats, exactly. Going the other way, one carat is 200 milligrams. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.
Every weight unit here
The whole group — 15 units with their symbols and the size of each one in kilograms — is on the conversion index, along with every pair it makes. The table above already gives each of them relative to a milligram.
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Questions people actually ask
- How many carats are in a milligram?
- 0.005. Exactly 200 milligrams, fixed by international agreement in 1907 after centuries of local carats. It weighs a gemstone; the karat that grades gold is a different word for a different thing — purity in twenty-fourths.
- How do I convert carats back to milligrams?
- Divide by 0.005, or multiply by 200 — they are the same operation.
Other weight conversions
Carats to milligrams — the same conversion the other way.