How to use the gold calculator
This calculator converts gold weight and purity into an international spot reference value. It helps estimate intrinsic gold value before you separately confirm a shop's labour charge, premium, buy-back quote and deductions.
Steps
- Enter a weight (e.g. 1, 5, 37.4).
- Pick a unit: gram, tael, mace or troy oz.
- Pick a product / purity (999.9 to 9K).
- Choose a display currency; conversion is shown only when a verified rate is available.
- Use the spot reference and weight conversion, then confirm the actual shop quote separately.
How it is calculated
Reference value = weight (tael) × spot gold per tael × purity × target-currency rate
Spot gold per tael = XAU/USD ÷ 31.1035 × 37.429 × USD/HKD.
Spot gold per tael = XAU/USD ÷ 31.1035 × 37.429 × USD/HKD.
Data is retrieved through the same-origin Cloudflare Worker with timeout, limited retry and last-success fallback. The calculator adds no manufactured shop premium or buy-back discount and is not any shop's official quote.
Hong Kong gold weight unit conversion
| Unit | Equals grams | Note |
|---|---|---|
| 1 troy ounce (oz) | 31.1035 g | International quote unit |
| 1 tael (HK troy tael) | 37.429 g | The "tael" HK shops use |
| 1 mace | 3.7429 g | 1 tael = 10 mace |
| 1 candareen | 0.374 g | 1 mace = 10 candareens |
| 1 gram | 1 g | International standard |
Buying vs selling — which price?
- Buying (you pay) = the shop's ask price, higher, including labour premium.
- Selling (you get) = the shop's bid price. Obtain comparable quotes for the same time, unit and purity, then compare net proceeds after deductions.
Results are public-market spot reference values / estimates, not any shop's official quote or actual dealing price and not investment advice. Confirm actual terms with the shop.
Read more: Gold market reference · Shop spread comparison · Bars vs jewellery