18K Gold Rate Calculator
Convert 24K market price to 18K purity instantly
Purity Multiplier:
75% (0.75)
Base 18K Rate (per gram):
0
Value for Weight:
0
Total Making Charges:
0
Tax Amount:
0
Final 18K Gold Price: 0
Understanding the 18 Carat Gold Calculation
Gold purity is measured in carats, with 24 carat (24K) being considered 99.9% pure gold. To calculate the price of 18 carat gold, we must first understand the ratio of purity. 18K gold contains 18 parts of pure gold and 6 parts of other metals (like copper, silver, or zinc) to increase durability.
Mathematical Formula:
Purity Ratio = 18 / 24 = 0.75 (or 75%)
18K Gold Rate = 24K Gold Rate × 0.75
Purity Ratio = 18 / 24 = 0.75 (or 75%)
18K Gold Rate = 24K Gold Rate × 0.75
Step-by-Step Calculation Guide
- Find the 24K Rate: Check the current market price for 99.9% pure gold per gram.
- Apply the Purity Factor: Multiply the 24K rate by 0.75. For example, if 24K is 6,000 per gram, the 18K base rate is 4,500.
- Add Making Charges: Jewelers charge for the labor of turning raw gold into jewelry. This is usually a flat fee per gram or a percentage.
- Include GST/Taxes: In many regions, a standard tax (like 3% GST in India) is applied to the sum of the gold value and making charges.
Example Calculation
If the 24K gold rate is 6,400 per gram and you want to buy a 10-gram 18K ring with making charges of 200 per gram:
- 18K Base Rate: 6,400 × 0.75 = 4,800 per gram
- Value for 10g: 4,800 × 10 = 48,000
- Making Charges: 200 × 10 = 2,000
- Subtotal: 48,000 + 2,000 = 50,000
- GST (3%): 50,000 × 0.03 = 1,500
- Total Price: 51,500
Why Choose 18K Over 24K?
While 24K is the purest form, it is extremely soft and prone to scratching or bending. 18K gold is preferred for diamond and gemstone jewelry because the 25% alloy content makes the metal strong enough to hold precious stones securely while maintaining a rich yellow luster.