Formula guide
How to Calculate Gold Price
The base formula starts with the international gold price in USD per troy ounce, then converts it into SGD per gram.
Current example
With the current reference of US$4,141.10 per troy ounce and USD/SGD 1.2917, the spot estimate becomes $171.98 per gram before purity. After purity, 999 becomes $171.80 per gram and 916 becomes $157.53 per gram.
1. Convert troy ounce to grams
One troy ounce equals 31.1034768 grams. This matters because international gold prices are often read in ounces, while Singapore buyers often want the value per gram.
2. Convert USD to SGD
Formula asas ialah SGD per gram = (USD per oz x USD/SGD) / 31.1034768.
If USD/SGD moves, the SGD per gram reading can change even when the gold price in USD has not moved much. That is why local prices need both readings: gold and exchange rate.
3. Adjust for purity
After the base price is calculated, multiply it by the purity multiplier. For example, 916 gold uses 0.916, 999 gold uses 0.999, and 22K uses 22/24.
| Purity | Multiplier | How to read it |
|---|---|---|
| 999 gold | 0.999 | Closer to spot, but premiums can still exist. |
| 916 gold | 0.916 | Relevant for many 22K jewellery items. |
| 18K gold | 0.750 | Base metal value is lower because gold content is lower. |
What to remember
This calculation estimates metal value, not shop price. Actual prices can be affected by premiums, spreads, making charges, relevant taxes, and item condition.
For a more practical reading, use the gold price calculator together with the spread, making charge, and premium page. The formula gives the base; transaction costs shape the number you finally see.