18K gold melt value calculator
Short answer
18K gold is 75 % pure gold (18 karat): 0.75 g of fine gold in every gram. Melt value is the weight of metal × 0.75 × the spot price per gram.
18K gold melt value calculator
Enter a weight and a stamp to see the sum.
Today's spot price: LBMA precious metal prices, Kitco live gold or your own dealer's quote. This page never contacts a price service.
Worked examples, with an example price
These figures use the example price of $4,046.30 per troy ounce, a snapshot of 2026-11-10 (source: api.gold-api.com). It is not a live price. Each row was computed by the same engine as the calculator.
| Weight | Fine gold | Melt value (example) |
|---|---|---|
| 1 g | 0.75 g | $97.57 |
| 2 g | 1.5 g | $195.14 |
| 5 g | 3.75 g | $487.84 |
| 10 g | 7.5 g | $975.69 |
| 20 g | 15 g | $1,951.37 |
| 1 troy ounce (31.1035 g) | 23.3276 g | $3,034.73 |
Reading the stamp
See what 18K means on jewelry. A stamp is a statement, not proof: confirm with an assay if the money matters.
Other melt-value pages
8K gold · 9K gold · 10K gold · 14K gold · 22K gold · 24K gold · sterling silver 925 · 800 silver · fine silver 999 · platinum 950 · palladium 950
Frequently asked
How much fine gold is in 18K gold?
0.75 g of fine gold per gram of metal (75 %).
How do I calculate the melt value of 18K gold?
Weight of metal × 0.75 × spot price per gram. The spot price per gram is the price per troy ounce divided by 31.1034768. It is melt value, not an appraisal.
How many grams is a pennyweight?
1 dwt = 1.55517384 g exactly (1/20 of a troy ounce).
Sources
- Arithmetic: karats / 24 × 1000 (no external source)
- Hallmarking Act 1973, Schedule 2 (revised text)
- Vienna Convention on precious metals, Technical Decisions Rev. 13 (in force 1 Oct 2026)
- Douane française, table of guarantee marks (2009)
All sources are listed with the method on the sources page.