Inputs
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Global benchmark price for pure gold (24k). 1 troy ounce = 31.1034768 g.
Use karat or set a custom fine percent below.
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Percent deducted from melt value.
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Results
Fine gold (g)
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Melt value
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Estimated payout
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Payout = Melt × (1 − margin) − flat fee − fee per gram × weight(g). Floor at zero.
Value vs. Purity
Instant chart of estimated payout for common karats using your inputs.
Example data table
| # | Spot/ozt ($) | Karat | Weight | Unit | Fine (g) | Melt ($) | Payout ($) |
|---|---|---|---|---|---|---|---|
| 1 | 2350 | 14k | 20 | g | — | — | — |
| 2 | 2350 | 18k | 10 | g | — | — | — |
| 3 | 2350 | 22k | 1 | oz | — | — | — |
Use the “Add current result to table” button to append your own line.
Formula used
Unit conversion: 1 troy ounce = 31.1034768 g, 1 dwt = 1.55517384 g, 1 grain = 0.06479891 g.
Fine fraction: f = max(0, min(1, customFine%/100)) if set, otherwise f = karat/24.
Price per gram (24k): P_g = spotPricePerOzt / 31.1034768.
Fine gold mass: m_f = weight_g × f.
Melt value: V_m = m_f × P_g.
Estimated payout: V_p = max(0, V_m × (1 − margin%) − fee_flat − fee_per_g × weight_g).
This model assumes linear fees and a constant discount to melt. Real offers may vary with lot size, assay uncertainty, location, and hedging costs.
How to use this calculator
- Enter the current spot price per troy ounce for pure gold.
- Set karat or specify a custom fine percent from an assay.
- Type weight and choose the unit (g, ozt, dwt, or grains).
- Adjust the margin and any fees that apply to your transaction.
- Click Calculate. Review fine grams, melt value, and payout.
- Use the chart to compare payouts across karats with your inputs.
- Append results to the table, then export CSV or PDF for records.
Tip: For multiple items, calculate each and append to the table before exporting.
FAQs
Karat indicates mass fraction of gold in 24 parts. For example, 18k is 18/24 = 75% gold. 14k is 14/24 ≈ 58.3% gold.
Grams (g), troy ounces (ozt), pennyweights (dwt), and grains (gr) are supported. All calculations internally convert to grams.
Buyers deduct a margin to cover refining, hedging, logistics, and profit. Margins often shrink for larger lots or higher-purity items.
Enter the assay fine percent in the custom field. The calculator will use it instead of the karat setting.
Outputs are estimates based on your inputs and simple fee assumptions. Actual offers vary by dealer, market timing, and assay method.
Yes. Calculate each item and click “Add current result to table.” Export the combined table as CSV or PDF.
No. Enter a spot price from your preferred source. For best results, update it before calculating.