Gold weight and cost calculator for jewellers
Enter the weight of a piece, its gold purity and the price per gram you pay, and see how much fine gold is in it and what the metal costs. It runs in your browser: nothing you type is sent or stored.
This calculator does not show a gold price. Use the price from your supplier or refiner. ELIPHASx's quote builder applies live metal prices for you automatically.
How the numbers are worked out
- Fine gold in the piece = weight × purity. A 6 g piece of 18ct (75%) holds 4.5 g of fine gold.
- Metal cost from the fine gold price = fine gold in the piece × the price per gram of fine gold, plus your loss allowance. It is an estimate: it values only the gold, not the alloy metals or what your supplier charges to refine and alloy it.
- Metal cost from your supplier's alloy price = weight × their price per gram for that alloy, plus your loss allowance. If you have this number, use it: it is closer to what you really pay.
Gold purity
| Gold | Fine gold | Typical hallmark |
|---|---|---|
| 9ct | 37.5% | 375 |
| 10ct | 41.7% | 417 |
| 14ct | 58.5% | 585 |
| 18ct | 75% | 750 |
| 22ct | 91.6% | 916 |
| 24ct | 99.9% | 999 |
Slips that cost money
- Mixing up units. Prices are often quoted per troy ounce. Divide by 31.1035 to get the price per gram.
- Using a retail price. A jeweller buying metal pays a trade price, which is different from what a shop charges a customer.
- Leaving out loss. Metal is lost in casting, filing and polishing. If you allow for it, show it as its own line.
- Using yesterday's price. The price moves every day, so a quote needs a validity date.
Want the whole quote, not just the metal?
Add stones, setting, design, making, finishing, markup and VAT, with the metal price applied for you. Your first quote is free and needs no account.
Build a quote free