Hi,
Have you ever looked at a gold jewelry item and noticed a tiny stamp that says “10K,” “14K,” or “22K”? Then you’ve come into contact with the karat system. But what does it signify exactly? And how do you convert karats into a percentage of pure gold?
At AU Bullion, we get a lot of questions from customers who are new to investing in gold or selling older jewellery. So, we’ve put together this simple guide to help you understand how karats work—and how to figure out how much pure gold is actually contained in your item.
What Is a Karat?
Karats (K) are a measure of the purity of the gold in an alloy. Pure gold is 24 karats, but most jewelry isn’t pure gold because it’s too soft to be worn every day. Therefore, gold is mixed with other metals (like copper or silver) to make it stronger.
Each karat is 1 part out of 24, so the higher the karat, the higher the gold content.
How to Convert Karat to Percentage
The conversion is straightforward. Simply divide the number of karats by 24, and multiply by 100 to get the percentage of pure gold.
Here’s the formula:
(Karat ÷ 24) × 100 = % of pure gold
Let’s examine it with some daily life examples:
| Karat | Formula | Pure Gold % |
| 24K | (24/24) x 100 | 100% |
| 22K | (22/24) x 100 | 91.6% |
| 18K | (18/24) x 100 | 75% |
| 14K | (14/24) x 100 | 58.3% |
| 10K | (10/24) x 100 | 41.7% |
| 9K | (9/24) x 100 | 37.5% |
Now you can easily say how much actual gold is present in any jewelry marked with karats!
Why It Matters
Knowing how to convert karat to percentage is important if you’re:
- Selling gold jewelry
- Buying gold items
- Getting an item appraised
- Investment in coins or bullion
Knowing the gold purity allows you to determine the true gold value and make informed choices—particularly if you’re looking to sell your gold.
What About Bullion?
Unlike jewelry, most bullion investment products (such as coins and bars) obviously state their gold content in millesimal fineness or percentages. For instance:
.9999 designates 99.99% pure gold (typically 24K)
.9167 = 91.67% pure gold (as used in 22K gold coins)
So when you’re dealing with bullion, you’re usually dealing with nearly pure gold with total transparency.
Ready to Test or Sell Your Gold?
At AU Bullion, we help you determine the true value of your gold—whether jewelry, coins, or scrap. Our experts use precise testing methods to assess karat and weight, and we make top-dollar payouts based on real-time market values. Do you have gold that you’d like to sell? We make it easy, secure, and simple. The next time you look at a gold item and notice “14K” or “18K,” you’ll know exactly how much gold is inside—and how to calculate its worth. If you ever need any help, AU Bullion is here to guide you.
