Gold · The Math
How Much Is Your Gold Worth Per Gram?
Spot price ÷ 31.1035 × karat purity × weight in grams. That is the entire calculation behind every honest gold offer — run it yourself below, then make any buyer show you theirs. We do it at the counter at 39 Avenue A as standard.
The Calculator
Melt Value Calculator
Melt value is not an offer. Every buyer — us included — pays below melt; the gap covers refining, risk, and margin. The difference between buyers is the size of that gap and whether they show it to you.
The Formula
How the Per-Gram Price Is Built
To calculate gold's value per gram: divide the spot price per troy ounce by 31.1035, multiply by the karat purity, then by the item's weight in grams. At $4,500 per ounce, pure gold is about $144.68 per gram, and 14K — which is 58.3 percent gold — is about $84 per gram.
A worked example: a 20-gram 14K chain contains about 11.66 grams of pure gold. At $4,500 spot, that is roughly $1,687 in melt value. An 18K piece of the same weight carries about $483 more, purely because of the higher purity.
Spot moves every trading day, which is why no honest page can print a permanent dollar figure. The calculator above does the arithmetic with whatever today's number is.
| Karat | Hallmark | Purity | Value per gram |
|---|---|---|---|
| 24K | 999 | 99.9% | $144.53 |
| 22K | 916 | 91.7% | $132.67 |
| 18K | 750 | 75.0% | $108.51 |
| 14K | 585 | 58.3% | $84.35 |
| 10K | 417 | 41.7% | $60.33 |
Figures shown at $4,500/oz spot. The table recalculates from the spot price field above. US 14K is 58.3% by definition; pieces hallmarked 585 are 58.5% — the same purity band.
The Honest Part
Why Every Offer Is Below Melt
Melt value is what the refined gold is worth on the market. Nobody pays you the full number, because the buyer has to refine the metal, carry the risk of spot moving against them, and keep the lights on. That part is normal and no reason for suspicion.
What should make you suspicious is a buyer who will not put the scale where you can see it, quotes a lump sum with no weight or purity attached, or prices in pennyweight without telling you what a pennyweight is. If you cannot reconstruct the offer from weight × purity × spot, you cannot compare it to anything.
Our standing suggestion: run your piece through this calculator before you sell anywhere — including to us. Then ask every buyer to show the same three numbers. The good ones will not hesitate.
Before You Weigh
Three Things That Skew the Number
Pennyweight quotes. One pennyweight (dwt) is 1.555 grams. Some shops quote in dwt because the unfamiliar unit makes offers hard to compare. Divide any dwt figure by 1.555 and you are back in grams.
Stones. Gemstones are not gold and do not belong on the scale. An honest buyer weighs around them or subtracts an estimate — and prices diamonds separately when they are worth something on their own.
Hollow pieces. A hollow rope or Cuban chain can look like 60 grams and weigh 12. The calculator is only as good as the weight you feed it, so use a kitchen scale at home for a rough number and expect the certified scale at the counter to settle it. More on that on the gold chains page.
