Carat to Milligram Converter
Convert Carat (ct) to Milligram (mg) instantly. 1 ct = 200 mg.
Mass Converter
26 units available
1 ct = 200 mg
Formula:
mg = ct × 200With your value: 1 ct = 200 mg
How big is that?
Everyday references on a logarithmic scale, all expressed in carat so you can sanity-check the result.
Other Carat to Milligram conversions
Carat to Milligram Conversion Table
| Carat (ct) | Milligram (mg) |
|---|---|
| 0.5 | 100 |
| 1 | 200 |
| 2 | 400 |
| 5 | 1,000 |
| 10 | 2,000 |
| 15 | 3,000 |
| 20 | 4,000 |
| 25 | 5,000 |
| 50 | 10,000 |
| 100 | 20,000 |
| 250 | 50,000 |
| 500 | 100,000 |
| 1000 | 200,000 |
Milligram to Carat Conversion Table
| Milligram (mg) | Carat (ct) |
|---|---|
| 0.5 | 0.0025 |
| 1 | 0.005 |
| 2 | 0.01 |
| 5 | 0.025 |
| 10 | 0.05 |
| 15 | 0.075 |
| 20 | 0.1 |
| 25 | 0.125 |
| 50 | 0.25 |
| 100 | 0.5 |
| 250 | 1.25 |
| 500 | 2.5 |
| 1000 | 5 |
Where these values come from
Every factor on this page is traced to the document that defines it. See the full provenance dataset or our methodology.
Carat (ct)
Mass
The metric carat is exactly 200 mg, agreed internationally in 1907.
National Institute of Standards and Technology (US) · Reviewed 2026-07-01
Milligram (mg)
Mass
Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).
Source: BIPM, The International System of Units (SI), 9th edition, 2019 (updated 2024)
Bureau International des Poids et Mesures · Reviewed 2026-07-01
How to Convert Carat to Milligram
To convert from Carat (ct) to Milligram (mg), multiply the value by 200.
Formula: mg = ct × 200
Reverse: ct = mg × 0.005
Step-by-Step Example
- Start with your value in Carat. For example: 5 ct
- Multiply by the conversion factor: 5 x 200
- The result is: 1,000 mg
About Carat
The carat equals 200 milligrams and is the standard unit for measuring gemstone weight.
Fun Fact: The word "carat" comes from the carob seed, which was used as a balance weight in ancient gem trading.
Common uses: gemstones, diamonds, jewelry.
About Milligram
The milligram equals one thousandth of a gram and is the standard unit for drug dosage and nutrient quantities.
Common uses: medication dosage, nutrition labels, laboratory work.
Frequently Asked Questions
How many Milligram are in 1 Carat?
There are exactly 200 Milligram in 1 Carat. This means the conversion factor from Carat to Milligram is 200.
What is the formula to convert Carat to Milligram?
The formula to convert Carat to Milligram is: mg = ct × 200. For example, to convert 10 Carat to Milligram, you would multiply 10 by 200.
What is a Carat?
The carat equals 200 milligrams and is the standard unit for measuring gemstone weight.
What is a Milligram?
The milligram equals one thousandth of a gram and is the standard unit for drug dosage and nutrient quantities.
What are the common uses of Carat?
The Carat is commonly used in gemstones, diamonds, jewelry.
Related Mass Conversions
Cite this page
UnitConvertLab. (2026). Carat to Milligram converter. UnitConvertLab. Retrieved from https://unitconvertlab.com/convert/carat-to-milligram