18K Gold
18K Gold Calculator
Free 18K gold calculator. Estimate 18-karat (75% pure) gold melt value by weight, live spot price, and payout percentage.
Use the calculatorAbout 18K gold
18-karat gold is 18 parts gold out of 24, or 75% pure gold by weight. It is common in higher-end jewelry, European pieces, and designer brands because it keeps a rich gold color while staying durable enough to wear.
At 75% purity, 18K is worth noticeably more per gram than 14K or 10K. Enter the weight below and the calculator converts to troy ounces and applies the live gold spot price.
Worked example at an illustrative gold spot of $4,000.00 per troy ounce (use the live price above for current figures):
How to calculate 18K gold value
- Weigh the item. Use a digital gram or pennyweight scale. Heavier, solid pieces give the most reliable estimate.
- Select the metal and purity. Pick gold, silver, or platinum, then choose the karat or fineness. Use Custom to enter an exact percentage.
- Confirm the live spot price. The calculator fills in the current spot price automatically. Edit it if you use a different quote.
- Calculate and adjust payout. Press Calculate to see the melt value, then move the payout slider to model a buying offer.
18K Gold Calculator questions
How much is 18K gold worth per gram?
At a gold spot of $4,000 per troy ounce, one gram of 18K gold holds about $96.45 in melt value (1 ? 31.1035 ? 0.75 ? $4,000). Use the live spot price above for an exact number.
Is 18K gold a good purity to sell?
18K carries strong melt value because it is 75% gold. Stamped, hallmarked 18K from a recognized maker can also carry resale value above melt for desirable pieces.
What is the difference between 18K and 750 gold?
They are the same thing. "750" is the millesimal stamp meaning 750 parts per thousand, which equals 18/24 = 75% gold.
Can I price mixed 18K and 14K lots together?
For accuracy, calculate each karat separately and add the items to the list. Mixing purities in one weight understates or overstates the total.