Carats Conversion

Scales are used to measure weight

The carat is a unit used to measure weight. Use one of the conversion calculators below to convert to another unit of measure, or read on to learn more about carats.

Carat Conversion Calculators

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Carat Definition and Usage

The carat is a unit of mass/weight equal to 200 milligrams.[1]

A carat is sometimes also referred to as a metric carat. Carats can be abbreviated as ct, and are also sometimes abbreviated as CD. For example, 1 carat can be written as 1 ct or 1 CD.

Background and Origin

Historically, various regions and countries have had their own version of the carat for use in measuring gold. The carat was standardized as a unit of a measure in 1877 and originally was equal to 205 milligrams of mass. It was later redefined at a convention in 1907 as being equal to 200 milligrams.

Uses

The carat is widely used for measuring the weight of diamonds, gemstones, and pearls.

Carats Measurement Conversion Table

Common carat values and equivalent imperial and metric weight measurements
carats tons pounds ounces metric tons long tons kilograms grams milligrams
1 ct 0.00000022046 t 0.000441 lb 0.007055 oz 0.0000002 t 0.00000019684 lt 0.0002 kg 0.2 g 200 mg
2 ct 0.00000044092 t 0.000882 lb 0.01411 oz 0.0000004 t 0.00000039368 lt 0.0004 kg 0.4 g 400 mg
3 ct 0.00000066139 t 0.001323 lb 0.021164 oz 0.0000006 t 0.00000059052 lt 0.0006 kg 0.6 g 600 mg
4 ct 0.00000088185 t 0.001764 lb 0.028219 oz 0.0000008 t 0.00000078737 lt 0.0008 kg 0.8 g 800 mg
5 ct 0.0000011023 t 0.002205 lb 0.035274 oz 0.000001 t 0.00000098421 lt 0.001 kg 1 g 1,000 mg
6 ct 0.0000013228 t 0.002646 lb 0.042329 oz 0.0000012 t 0.000001181 lt 0.0012 kg 1.2 g 1,200 mg
7 ct 0.0000015432 t 0.003086 lb 0.049384 oz 0.0000014 t 0.0000013779 lt 0.0014 kg 1.4 g 1,400 mg
8 ct 0.0000017637 t 0.003527 lb 0.056438 oz 0.0000016 t 0.0000015747 lt 0.0016 kg 1.6 g 1,600 mg
9 ct 0.0000019842 t 0.003968 lb 0.063493 oz 0.0000018 t 0.0000017716 lt 0.0018 kg 1.8 g 1,800 mg
10 ct 0.0000022046 t 0.004409 lb 0.070548 oz 0.000002 t 0.0000019684 lt 0.002 kg 2 g 2,000 mg
11 ct 0.0000024251 t 0.00485 lb 0.077603 oz 0.0000022 t 0.0000021653 lt 0.0022 kg 2.2 g 2,200 mg
12 ct 0.0000026455 t 0.005291 lb 0.084658 oz 0.0000024 t 0.0000023621 lt 0.0024 kg 2.4 g 2,400 mg
13 ct 0.000002866 t 0.005732 lb 0.091712 oz 0.0000026 t 0.0000025589 lt 0.0026 kg 2.6 g 2,600 mg
14 ct 0.0000030865 t 0.006173 lb 0.098767 oz 0.0000028 t 0.0000027558 lt 0.0028 kg 2.8 g 2,800 mg
15 ct 0.0000033069 t 0.006614 lb 0.105822 oz 0.000003 t 0.0000029526 lt 0.003 kg 3 g 3,000 mg
16 ct 0.0000035274 t 0.007055 lb 0.112877 oz 0.0000032 t 0.0000031495 lt 0.0032 kg 3.2 g 3,200 mg
17 ct 0.0000037479 t 0.007496 lb 0.119931 oz 0.0000034 t 0.0000033463 lt 0.0034 kg 3.4 g 3,400 mg
18 ct 0.0000039683 t 0.007937 lb 0.126986 oz 0.0000036 t 0.0000035431 lt 0.0036 kg 3.6 g 3,600 mg
19 ct 0.0000041888 t 0.008378 lb 0.134041 oz 0.0000038 t 0.00000374 lt 0.0038 kg 3.8 g 3,800 mg
20 ct 0.0000044092 t 0.008818 lb 0.141096 oz 0.000004 t 0.0000039368 lt 0.004 kg 4 g 4,000 mg

References

  1. National Institute of Standards and Technology, Precious Metals Conversion Information, https://www.nist.gov/pml/weights-and-measures/laws-and-regulations/precious-metals-conversion