Convert Carats to Micrograms
1 carat is 200,000 mcg. One carat is exactly 200000 micrograms.
One carat is 200000 micrograms. To convert carats to micrograms, multiply by 200000; to go the other way, divide by 200000 or multiply by 5.0000 × 10^-6. The factor is exact rather than rounded: it follows from NIST Handbook 44. Exactly 200 milligrams, fixed by international agreement in 1907 after centuries of local carats.
Factor checked against the defining standard · How we check
- Carats × 200000
1 * 200000200,000 mcg
1 carat in every weight unit
| Unit | Value | Exact factor |
|---|---|---|
| ounces | 0.00705479239 oz | × 0.00705479238992 |
| pounds | 0.0004409245244 lb | × 0.00044092452437 |
| stone | 0.00003149460888 st | × 0.0000314946088836 |
| US tons | 0.0000002204622622 ton | × 0.000000220462262185 |
| micrograms | 200,000 mcg | × 200,000 |
| milligrams | 200 mg | × 200 |
| centigrams | 20 cg | × 20 |
| grams | 0.2 g | × 0.2 |
| kilograms | 0.0002 kg | × 0.0002 |
| slugs | 0.00001370435317 slug | × 0.0000137043531714 |
| tonnes | 0.0000002 t | × 0.0000002 |
| carats (as entered) | 1 ct | — |
| troy ounces | 0.006430149314 ozt | × 0.00643014931373 |
| grains | 3.086471671 gr | × 3.08647167059 |
| long tons | 0.0000001968413055 LT | × 0.000000196841305522 |
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 carats to micrograms? The converter and the working
- 1.Take the measurement in carats.
- 2.Multiply by 200000 — that is how many micrograms fit in one carat.
- 3.To go back the other way, divide by 200000, or multiply by 5.0000 × 10^-6.
Worked example: 25 carats to micrograms
- Formula
- ct × 200000 = mcg
- Arithmetic
- 25 × 200000 = 5,000,000 mcg
- Answer
- 25 ct = 5,000,000 mcg
The factor is exact, so this figure is exact too — only the display is rounded.
Carats to micrograms conversion table
| Carats | Micrograms |
|---|---|
| 1 ct | 200,000 mcg |
| 2 ct | 400,000 mcg |
| 3 ct | 600,000 mcg |
| 4 ct | 800,000 mcg |
| 5 ct | 1,000,000 mcg |
| 6 ct | 1,200,000 mcg |
| 7 ct | 1,400,000 mcg |
| 8 ct | 1,600,000 mcg |
| 9 ct | 1,800,000 mcg |
| 10 ct | 2,000,000 mcg |
| 12 ct | 2,400,000 mcg |
| 15 ct | 3,000,000 mcg |
| 20 ct | 4,000,000 mcg |
| 25 ct | 5,000,000 mcg |
| 50 ct | 10,000,000 mcg |
| 100 ct | 20,000,000 mcg |
| 200 ct | 40,000,000 mcg |
| 300 ct | 60,000,000 mcg |
| 500 ct | 100,000,000 mcg |
| 1000 ct | 200,000,000 mcg |
| 2000 ct | 400,000,000 mcg |
| 5000 ct | 1,000,000,000 mcg |
| 10000 ct | 2,000,000,000 mcg |
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.
What is a microgram?
One millionth of a gram. Written mcg rather than µg on labels deliberately: the Greek letter is the character most often lost in transcription, and a factor of a thousand in a dose is not a rounding error.
How many micrograms are in a carat?
One carat is 200000 micrograms, exactly. Going the other way, one microgram is 5.0000 × 10^-6 carats. 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 carat.
Cite this page
- APA
- Rule Calculator. (2026). Convert Carats to micrograms. Rule Calculator. https://rulecalculators.com/convert/carat-to-microgram
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- Chicago
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Questions people actually ask
- How many micrograms are in a carat?
- 200000. One millionth of a gram. Written mcg rather than µg on labels deliberately: the Greek letter is the character most often lost in transcription, and a factor of a thousand in a dose is not a rounding error.
- How do I convert micrograms back to carats?
- Divide by 200000, or multiply by 5.0000 × 10^-6 — they are the same operation.
Other weight conversions
Micrograms to carats — the same conversion the other way.