Enter a karat value (e.g., 10K, 14K, 18K, 22K, or 24K) to see the approximate decimal fineness and percentage purity of gold.
About Karat and Fineness
Gold purity is often expressed in karats (K) or fineness.
24K = 99.9% pure (fineness ~ 0.999)
18K = 75% pure (fineness 0.750)
14K = 58.3% pure (fineness 0.583)
10K = 41.7% pure (fineness 0.417)
Historical Insights
The karat system has roots in ancient coinage weight standards.
Over centuries, jewelers have used karats to denote the ratio of pure gold in an alloy.
In Europe, decimal fineness (like 0.585) is more common, while the U.S. often uses karats.
FAQ: Karat & Purity
1. Which is more accurate, karat or fineness?
Both measure the same concept. Karat is out of 24; fineness is a decimal out of 1.000.
2. Is 24K always 100% pure?
24K is typically around 99.9% pure (sometimes marked 0.999 or 0.9999).
Absolute 100% purity is rare due to trace impurities.
3. Can I use this for silver or platinum?
Karat rating is unique to gold. Silver uses sterling (0.925) or fine (0.999),
while platinum is usually indicated by Pt purity.
4. Is 14K gold better than 10K?
"Better" can be subjective. 14K is purer and slightly more valuable,
but 10K can be more durable. It depends on preference and usage.
5. Why do jewelers prefer certain karats?
Higher karats have more gold but are softer. Lower karats can be more durable
and cost-effective for jewelry.
Testimonials and Reviews
Alice, Jeweler:
"This karat-to-fineness calculator helps me ensure I'm labeling my pieces accurately for my customers."
Thomas, Collector:
"Great for quickly checking the exact percentage of gold in older jewelry marked 18K or 22K."
