How this gold to USD calculator works
This tool converts your gold holdings into an estimated U.S. dollar value using four core inputs: weight, unit, purity, and spot price. If you buy or sell through a dealer, you can also include a premium (or discount) percentage to get a more realistic number.
Whether you are valuing jewelry, coins, bars, or scrap metal, the same principle applies: first determine the amount of pure gold, then multiply by the current market price.
Gold to USD formula
Step 1: Convert weight to troy ounces
Gold is globally priced in troy ounces, not regular ounces. The calculator automatically converts grams, kilograms, and avoirdupois ounces into troy ounces.
- 1 troy ounce = 31.1034768 grams
- 1 regular ounce = 28.349523125 grams
- 1 kilogram = 1000 grams
Step 2: Adjust for purity
Not all gold items are pure 24K. For example, 18K gold is 75% pure. So pure gold content = total troy ounces × purity factor.
Step 3: Multiply by spot price
Market value (USD) = pure troy ounces × spot price (USD per troy ounce). Then apply any premium or discount:
Final value = market value × (1 + premium% / 100)
Quick purity reference
| Karat | Purity % | Decimal Factor |
|---|---|---|
| 24K | 99.9% | 1.000 |
| 22K | 91.67% | 0.9167 |
| 18K | 75.0% | 0.750 |
| 14K | 58.5% | 0.585 |
| 10K | 41.7% | 0.417 |
Example calculation
Suppose you own 50 grams of 22K gold, and spot price is $2,350/ozt.
- 50 g = 1.6075 troy oz (gross)
- Pure gold = 1.6075 × 0.9167 = 1.4736 troy oz
- Market value = 1.4736 × 2350 = $3,462.96
If your dealer offers 2% below spot, estimated payout becomes about $3,393.70.
What affects your final cash value?
- Spot price volatility: Gold can move significantly in a single day.
- Buy/sell spread: Dealers typically sell above spot and buy below spot.
- Form factor: Coins and branded bars may command higher resale premiums.
- Assay/testing: If purity is uncertain, the buyer may reduce the quote.
Frequently asked questions
Is this calculator for jewelry too?
Yes. Just enter the jewelry weight and select the correct karat purity. Keep in mind that jewelers may also charge design and workmanship premiums that are not part of raw gold value.
Why use troy ounces instead of normal ounces?
Precious metals are conventionally priced in troy ounces. A troy ounce is heavier than a regular ounce, so using the right unit is essential.
Does this show live gold prices?
This page uses the value you enter. For best accuracy, paste in the latest spot price from your preferred market source before calculating.
Bottom line
A reliable gold to USD estimate starts with correct unit conversion and purity adjustment. Use this calculator whenever you want to check the current value of your gold holdings, compare dealer offers, or plan a buy/sell decision with clearer numbers.