How to calculate the value of your gold step by step
With three numbers, the weight, the karat and today's price, you can work out what any piece of gold is worth. Here is the formula with worked examples.
The formula
Purity is expressed as a decimal: 24K = 0.999 (or 1 for quick estimates), 18K = 0.750, 14K = 0.585 and so on. See the full table in the karat guide.
Step 1: get the price per gram of fine gold
Take the spot price per ounce and divide it by 31.1035. For another currency, multiply by today's exchange rate. Our home page does this automatically.
Step 2: weigh the piece
Use a scale that reads grams to at least two decimals. If the piece has stones, pearls or other materials, their weight is not gold, so deduct it or ask for an estimate.
Step 3: confirm the karat
Check the hallmark and, if possible, confirm it with a test. A karat error changes the result a lot: the difference between 14K and 18K is more than 28% of the value.
Examples
These examples use an illustrative price of $130 per gram of fine gold. Replace it with today's price.
An 18K chain weighing 12 grams
A 14K ring weighing 4.5 grams
A 1-ounce 24K bar
From melt value to selling price
The result is the value of the gold content, the maximum reference. A buyer will pay a percentage of it. Knowing the exact figure lets you compare offers and spot an excessive discount. See our guide on how to sell gold for the best price.
Prefer not to do the math? The calculator does it all with the live price and in your currency.