Carat (ct) - Unit Information & Conversion
What is a Carat?
Definition
The carat is a unit of mass used for measuring gemstones and pearls. It is defined as exactly 200 milligrams (0.2 grams).
History
The term "carat" comes from the carob seed ("keration" in Greek), which was historically used as a standard for weighing small quantities due to its perceived uniform weight. The metric carat of 200 mg was adopted internationally in 1907.
Common Uses
- Jewelry Industry: The primary unit for weighing diamonds and other precious gemstones.
- Pearls: Used for weighing pearls.
- Note: This is distinct from "karat," which measures the purity of gold.
Unit FAQs
How many milligrams are in a carat?
There are exactly 200 milligrams (mg) in 1 carat (ct).
How many grams are in a carat?
There are 0.2 grams (g) in 1 carat (ct).
Is carat the same as karat?
No. Carat (ct) measures mass (weight) for gemstones, while Karat (K or kt) measures the purity of gold (e.g., 24K gold is pure gold).
Carat Conversion Formulas
To Kilogram:
To Gram:
To Milligram:
To Pound:
To Ounce:
To Stone:
To Ton (metric):
To Ton (US):
To Ton (UK):
To Microgram:
To Slug:
To Troy Ounce:
To Pennyweight:
To Grain:
To Dram:
To Quintal:
To Atomic Mass Unit:
To Pavan (India):
To Kati (India):
To Masha (India):
To Dina (India):
To Pras (India):
To Lota (India):
Convert Carat
Need to convert Carat to other weight units? Use our conversion tool.