Gold Karat Purity Calculator
Compare gold karat levels, understand purity percentages, and calculate the value difference between karats.
Karat Value Comparison
Compare the gold content and value between two karat levels.
Purity Converter
Convert between karat, percentage, fineness, and millesimal stamps.
Durability vs Value Trade-off
See how karat level affects both intrinsic value and practical durability for jewelry.
Formula
Millesimal Fineness = (Karat / 24) × 1000 (e.g., 18k = 750)
Frequently Asked Questions
What is the difference between 14k and 18k gold?
Which gold karat is best for jewelry?
How can I tell what karat my gold is?
Understanding Gold Karat Purity
The karat system measures gold purity on a scale of 1 to 24, where 24 karat represents pure gold (99.9%). Each karat unit represents 1/24th of the total composition. So 18 karat gold contains 18 parts gold and 6 parts other metals (typically silver, copper, zinc, or palladium). The remaining metals are called "alloys" and serve to improve hardness, color, and workability.
Different regions have different karat preferences. In the United States, 14k is the most popular for everyday jewelry due to its balance of durability and gold content. European fine jewelers favor 18k, which is considered the standard for luxury pieces. In India, the Middle East, and Southeast Asia, 22k and 24k gold is preferred for both jewelry and investment purposes.
The alloy composition also determines gold color. Yellow gold uses silver and copper in balanced proportions. Rose gold uses a higher copper ratio, creating its distinctive warm pink hue. White gold uses palladium, nickel, or silver to achieve a silvery appearance and is often plated with rhodium for a bright white finish. Each color variant can be produced at any karat level, though the color saturation varies with gold content.