Gold Per Gram Calculator
Enter the current gold spot price and your item details to estimate value per gram and total melt value.
How this gold per gram calculator works
Gold is quoted globally in troy ounces, but most people buy and sell jewelry in grams. This calculator bridges that gap by converting spot price per troy ounce into a gram-based value and then adjusting for purity.
It is especially useful when you want to quickly estimate whether an offer from a jeweler, pawn shop, or gold buyer is reasonable. You can also model premiums and discounts to compare buying vs. selling prices.
Core formula
The calculation follows these steps:
- 24K price per gram (USD) = Spot price per ounce ÷ 31.1034768
- Purity factor = Karat ÷ 24
- Your gold price per gram (USD) = 24K gram price × Purity factor
- Melt value (USD) = Your gold price per gram × Weight in grams
- Adjusted value (USD) = Melt value × (1 + Premium/Discount %)
- Local currency values = USD values × FX rate
Gold purity reference (karat to pure gold content)
- 24K = 99.9% pure (factor 1.000)
- 22K = 91.7% pure (factor 0.917)
- 18K = 75.0% pure (factor 0.750)
- 14K = 58.3% pure (factor 0.583)
- 10K = 41.7% pure (factor 0.417)
Example calculation
Suppose spot gold is $2,350 per troy ounce, you own a 12 gram 18K ring, and a buyer offers 7% below melt.
- 24K gram price: 2350 ÷ 31.1034768 = $75.55
- 18K gram price: $75.55 × 0.75 = $56.66
- Melt value: $56.66 × 12 = $679.92
- Buyer payout at -7%: $679.92 × 0.93 = $632.33
This gives you a practical benchmark before negotiating.
What can make real-world prices different?
1) Spread and processing costs
Buyers need margin for refining, labor, and market risk. That is why selling prices are usually below melt value.
2) Brand and craftsmanship
Fine jewelry can carry design value beyond metal content. Melt value is only one part of total value.
3) Market volatility
Spot prices move throughout the trading day. A quote in the morning may not match one in the afternoon.
4) Testing and verification
If purity is uncertain, a buyer may test and downgrade the effective karat level, reducing payout.
Tips for using this calculator effectively
- Use a current live spot price from a reliable market source.
- Weigh items accurately, preferably on a scale with 0.01g precision.
- Separate stones or non-gold parts before estimating melt value.
- Get multiple quotes from local and online buyers.
- Use the premium/discount field to compare offers quickly.
Frequently asked questions
Is this price what I will definitely get paid?
No. It is an estimate based on spot price, purity, and weight. Actual offers depend on buyer policies and testing.
Why does the calculator use troy ounces?
Global precious metal markets quote gold in troy ounces. One troy ounce equals 31.1034768 grams.
Can I use this outside the U.S.?
Yes. Enter your local FX conversion in the currency field to view translated values.
Bottom line
A good gold per gram estimate helps you make smarter decisions whether you are buying jewelry, selling scrap, or just tracking value. Use this tool as your quick benchmark, then compare real offers to avoid leaving money on the table.