Gold Calculator

How the calculation works

Gold value comes down to three numbers: how much your item weighs, how pure the gold in it actually is, and the current market price of pure gold. Jewelry is almost never 100% gold. It is an alloy, gold mixed with other metals like copper, silver or zinc for strength and color, and the karat number tells you what fraction of that alloy is actually gold.

The calculator takes your weight, converts it to grams if you entered a different unit, multiplies by the purity fraction for your selected karat (18K is 75% gold, for example), and multiplies that pure gold weight by the price per gram. The price per gram is derived from the live troy ounce price, since gold is quoted per troy ounce (31.1034768 grams) in every market worldwide, not per gram.

• Weight in grams, troy ounces, pennyweight (dwt) or grains, converted automatically
• Karat purity from 24K (99.9% pure) down to 9K (37.5%), or type a custom percentage
• Live gold price fetched automatically, or type your own if you already have a quote
• Shows the pure gold content in grams alongside the dollar value, not just a single number

Worked example: a 14K gold ring

Say you have a 14K gold ring that weighs 5.2 grams on a kitchen scale. 14K gold is 58.3% pure gold (the rest is alloy metal). If the live gold price is $4,600 per troy ounce, the price per gram of pure gold works out to $4,600 divided by 31.1034768, which is about $147.89 per gram.

Multiply that by the purity: $147.89 times 0.583 gives roughly $86.22 per gram of 14K gold. Multiply by the 5.2 gram weight and the ring's melt value comes out to around $448. That is the melt value of the gold itself, not a jewelry store's retail price and not what a scrap buyer will actually pay you (see the note on dealer payouts below).

Worked example: 22K gold coin in grams and troy ounces

A 1 troy ounce 22K gold coin (a common weight for bullion coins like the Krugerrand) contains 91.6% pure gold. At $4,600 per troy ounce, a full troy ounce of 24K gold is worth $4,600, so the 22K coin's gold content is worth 91.6% of that: about $4,213.60. You can enter the weight as "1" with the unit set to troy ounce and the karat set to 22K to check this directly, no need to convert to grams by hand first.

Worked example: mixed scrap in grams, 10K

Scrap gold rarely comes as one clean item. Say a small dish of broken chains, single earrings and a class ring weighs 18.4 grams total on a jewelry scale, and everything in the dish is stamped 10K (the most common karat for older, more affordable US jewelry). At $4,600 per troy ounce, 10K gold's purity of 41.7% puts the price per gram at roughly $61.67. Multiply that by 18.4 grams and the batch is worth around $1,135 in melt value. If the dish actually contains a mix of karats, weigh and calculate each karat group separately rather than averaging, since the purity difference between a 10K and an 18K item is large enough to matter.

Quick reference: what different weights are worth by karat

These figures use a spot price of $4,600 per troy ounce as an example so you can sanity-check the calculator's output before you enter your own numbers. Your actual result will differ as the live price moves, use the calculator above for a current figure, or see the gold price per gram page for a live per-gram breakdown by karat without doing the multiplication yourself.

Common types of scrap and jewelry gold this calculator handles

The weight-times-purity-times-price formula works the same way regardless of what shape the gold is in, only the karat and weight change.

• Broken or single-piece jewelry: chains, rings, earrings, pendants, usually 10K to 18K in the US
• Dental gold: crowns and bridges are often 16K or higher, weigh separately from other items since dental alloys sometimes include other precious metals
• Bullion coins and bars: typically 22K or 24K, weight is usually printed or stamped precisely
• Class rings and vintage jewelry: commonly 10K, look for a stamp before assuming the karat
• Gold-filled or gold-plated items: these are NOT solid gold and this calculator will overstate their value if you enter the item's full weight, see the note below

A note on gold-filled and gold-plated items

Gold-filled and gold-plated jewelry are not solid gold, they are a base metal (often brass) with a thin layer of gold bonded or plated on the surface. A stamp reading "GF", "HGE", "GP" or "14K GF" (rather than a plain "14K") is a signal you're looking at plated or filled gold, not solid. Running the full item weight through this calculator as if it were solid karat gold will give a wildly inflated result, since the actual gold content by weight is a tiny fraction of the total. If you're not sure whether an item is solid or plated, a jeweler's acid test or an electronic tester (mentioned above) can tell the difference in seconds.

Why the gold price changes throughout the day

Gold trades on global markets almost around the clock, and the spot price this calculator uses moves with that trading, sometimes by small amounts within minutes. A few of the bigger drivers behind those moves: central bank interest rate decisions (gold tends to become more attractive when interest rates on cash and bonds are low), inflation expectations (gold is often bought as a hedge when investors expect the dollar's purchasing power to fall), the strength of the US dollar itself (gold is priced in dollars worldwide, so a weaker dollar often means a higher gold price and vice versa), and demand from jewelry markets and central banks, which shifts with the seasons and with global events.

None of that changes how this calculator works, it just explains why the number in the price field is different if you check back tomorrow. If you're planning to sell, checking the price at a couple of different times of day, or across a few days, can tell you whether it's trending up or down before you commit.

What a scrap gold buyer will actually pay you

The number this calculator shows is the melt value, the raw market value of the pure gold content at today's spot price. A pawn shop, jeweler or refiner will pay you less than that, because they need a margin to cover their own costs and profit. It is normal, not a scam, for an offer to land somewhere between roughly 60% and 90% of melt value, depending on the buyer and how much gold you are selling.

Refiners who process large volumes (see the gold purity chart for how fineness stamps work) typically pay closer to melt value than a local pawn shop does, because they are not marking up for resale, they are extracting and reselling the raw metal. If an offer comes in under half of what this calculator shows, it is worth getting a second quote before you sell.

How to weigh gold accurately at home

A kitchen scale that measures in grams is enough for a rough estimate, but jewelry scales built for precious metals (often under $20) measure to 0.01 gram and matter more than you might expect: a 2 gram item that is actually 1.9 grams is a 5% error before you even get to the karat and price. If your scale only shows ounces, remember that a troy ounce (used for gold) is about 10% heavier than the everyday avoirdupois ounce used for food, so switch the calculator's unit to troy ounce rather than converting a regular ounce reading by hand.

• Zero (tare) the scale with nothing on it before weighing
• Remove stones, clasps and non-gold parts where you can, they don't add gold value and can throw off the weight
• Weigh in grams if your scale supports it, it's the most precise common unit
• If your item is stamped with a karat number (like "14K" or "585"), use that rather than guessing

Reading a karat stamp

Most real gold jewelry is stamped somewhere discreet, inside a ring band or on a clasp, with either a karat number (10K, 14K, 18K) or a three-digit fineness number (417, 585, 750). These mean the same thing: 585 is the fineness stamp for 14K, 750 is the fineness stamp for 18K. If you can't find a stamp, or you're not sure it's genuine, a basic acid testing kit or an electronic gold tester can confirm the karat before you rely on this calculator's result. See the gold purity chart for the full karat-to-fineness table.