Gold Weight Calculator
Work out the weight of a bar, a round wire, a sheet, a flat ring band or a chain from the measurements. The weight is the main result, and a checkbox adds the melt value at today's price.
Gold weight
A rectangular block: length × width × height. Rounded edges make the real bar lighter.
Pure gold, 19.32 g/cm³ at 20°C. The cited sheet’s range is 19.13–19.51.
The dollar line uses 24 ÷ 24. The weight line uses the density above.
On this page
Weight is volume times density. Pure gold is 19.32 grams per cubic centimetre at 20°C. Alloy densities on this page are approximate, and every result is an estimate until you weigh the real piece.
How gold weight is calculated
A scale reads mass. A drawing only gives you size. Density is the bridge: how many grams of that metal sit in one cubic centimetre. Turn the measurements into a volume and multiply by the density of the alloy. The product is grams. Pennyweight and troy ounces are that same mass in the units jewelers and bullion dealers use. One pennyweight is 1.55517384 grams. One troy ounce is 31.1034768 grams. A kitchen ounce, 28.35 grams, is a different unit.
Every length is in millimetres. A cubic centimetre is 1,000 cubic millimetres, so divide the millimetre volume by 1,000 before multiplying by density. A bar 10 mm by 10 mm by 1 mm is 0.1 cubic centimetres. At the pure-gold density that is 1.932 grams. The same bar in a lighter alloy weighs less. A bar or block is length times width times height. A sheet is the same product. A round wire is the area of its circle times its length. A ring is a flat band of constant width. A chain is the box around the links times a fill factor you type. None of those steps looks up a weight for “a size 7.”
Density of gold and of common alloys
Pure gold has a specific gravity of 19.32 at 20°C. That figure is given in the Geological Survey of Canada chapter “Chemistry, mineralogy and geochemistry of gold,” and it is the same number in the element table of the Kassoy sheet “Precious metals for jewelry.” The alloy rows are the copper-and-silver column of that sheet, with the range printed beside it. The sheet calls the values theoretical and says finished ornaments tend to be less dense. White gold and rose gold use different added metals, so they do not share one density. 9K is not on the sheet, and this page does not invent a 9K number. Use the custom field when you have a density from a caster or a lab.
| Karat | Fineness on the sheet | Density used here | Range on the sheet |
|---|---|---|---|
| 24K | 1000/1000 | 19.32 g/cm³ | 19.13–19.51 |
| 22K | 916/1000 | 17.73 g/cm³ | 17.45–18.24 |
| 18K | 750/1000 | 15.24 g/cm³ | 14.84–16.12 |
| 14K | 584/1000 | 13.38 g/cm³ | 12.91–14.44 |
| 10K | 417/1000 | 11.91 g/cm³ | 11.42–13.09 |
Source: Kassoy, “Precious metals for jewelry” density sheet, copper-and-silver column, plus the pure-gold figure above. These are labelled approximate. A human should check the sheet before treating a row as exact.
The 14K row is where two conventions meet. The density sheet lists 14K as 584 parts per thousand and a copper-and-silver density of 13.38 g/cm³, inside 12.91 to 14.44. The value pages on this site price 14K as 14 divided by 24, which is 58.3 percent, while a 585 stamp is 58.5 percent. The weight line uses the density. The optional dollar line uses karat divided by 24. A 14K bar and a 24K bar of the same size do not weigh the same, because 13.38 is well below 19.32.
On that same column, 10K is 11.91 g/cm³ (range 11.42–13.09), 18K is 15.24 (14.84–16.12), and 22K is 17.73 (17.45–18.24). The sheet’s copper-only column is lower and its silver-only column is higher. This calculator uses the middle column and shows the range under the menu. For a known white-gold recipe, type the density you were given.
Bars, wire and sheet
A cast bar or a flat sheet is the honest case: square corners and a caliper on every side. Measure twice and keep the smaller reading if the piece is out of square. A rounded poured bar is not a box, so the outside measurements count corners that are missing. Weigh that lump. An oval wire has two diameters; if they disagree, weigh a known length. A 0.5 mm sheet and a 0.4 mm sheet are 20 percent apart in weight, so use a micrometer, and flatten wrinkled foil before you measure it.
Rings, from a US size
A ring size is an inside measurement, not a weight. The rule used here is the one on common US conversion charts: size 0 has an inside diameter of 11.63 mm, and each whole size adds 0.8128 mm (0.032 inch). Size 7 is 17.32 mm. That matches the millimetre column of the Jewelersoul chart and the Merkez Atölye chart. Rio Grande’s chart differs by a few hundredths of a millimetre at some sizes. ISO 8653 defines size by inner circumference in millimetres. It is not the US scale, and this page does not treat the US formula as that standard. The diameter is computed from the rule above, not from a weight-by-size table.
Width runs along the finger. Thickness is the radial thickness, from the inside of the shank to the outside. Volume is pi times thickness times (inside diameter plus thickness) times width, which is exact for a flat band of constant section. It is the wrong shape for a comfort-fit band, a knife edge, or a shank that narrows under the head. Those rings can sit several tenths of a gram away from the flat-band figure, so the result stays labelled an estimate.
Chains and the fill factor
Length, width and thickness describe a box, and most of that box is empty. The fill factor is the share that is metal. One means a solid bar of those dimensions, which overstates a hollow curb or a rope chain. There is no default and no menu of curb, figaro or rope factors. Those styles are made hollow, solid and in more than one wire size, so a single factor would be an invented table. Typing 40 is read as 40 percent. If you have weighed one chain of the same style, divide that weight by the solid-box weight and reuse the factor on the next length. A clasp is extra. When the factor is a guess, weigh the chain.
How to weigh jewelry at home
For a ring or a pair of earrings, use a scale that shows 0.01 g. A kitchen scale that steps in whole grams will call a 2.4 gram band and a 2.6 gram band the same object. Put a cup or a folded piece of paper on the platform, press tare, then set the piece in the cup so a ring cannot roll off and a chain cannot drape onto the counter. Weigh it twice. If the readings differ by more than one step, move away from a vent or a wobbling table and try again.
Stones, enamel, steel springs and a watch movement are not gold, and a home scale cannot separate them. Leave a stone in place if you cannot unseat it safely, and treat the reading as the piece plus the stone. A magnet only screens for steel. For a sale, a shop with a pennyweight scale and an acid test or an XRF gun is the check that matters. Divide grams by 1.55517384 if the buyer quotes in pennyweight.
Why this page has no typical ring or chain weight
Lists that say a size 7 band “usually” weighs a certain amount rarely name the alloy, the width, the thickness or the comfort-fit they measured, and they do not agree with each other. A hollow chain can weigh a fraction of a solid chain with the same outside size. Stones, solder and the fill of the links move the number more than a chart can. Printing a range here would mean inventing one. Measure the piece, or weigh it. Grams, pennyweight and troy ounces are three readings of that one estimate, and each one carries the same line: estimate, weigh the real piece.
The optional value
The weight does not need a gold price. The checkbox adds a melt value from the spot price on the calculator and from karat divided by 24. It is labelled an estimate of melt value, not an offer. A buyer pays less than melt after testing and a margin. A custom density does not tell you the purity, so you pick the karat for that dollar line yourself. Leave the checkbox off when all you wanted was the weight.
Gold Weight Calculator questions
How do you calculate the weight of gold from its size?
Multiply the volume in cubic centimetres by the density in grams per cubic centimetre. Measure in millimetres, divide by 1,000, then multiply by the density. Pennyweight is grams divided by 1.55517384. Troy ounces are grams divided by 31.1034768.
Why is 14K lighter than 24K of the same size?
14K is 14 parts gold in 24. The rest is lighter metal. The Kassoy density sheet puts a copper-and-silver 14K alloy near 13.38 g/cm³, against 19.32 for pure gold at 20°C. Same volume, lower weight. The sheet also prints a range and says finished pieces tend to be less dense than the theory.
How does this page turn a US ring size into a diameter?
Size 0 is an inside diameter of 11.63 mm, and each whole size adds 0.8128 mm. Size 7 is 17.32 mm. That matches the Jewelersoul and Merkez Atölye charts. Rio Grande’s chart differs by a few hundredths of a millimetre. The band is then a flat rectangle. A comfort-fit or tapered ring is a different shape.
What is a chain fill factor?
It is the share of the chain’s outer box that is metal. A factor of 1 is solid metal. A hollow chain is lower, and curb, rope and figaro are not one number. If you weighed a similar chain, divide that weight by the solid-box weight. Otherwise weigh the chain.
Do stones count in the calculated weight?
No. These shapes are metal only. A stone, a setting or a clasp is mass the measurements do not see. Weigh the piece, and ask a jeweler what the stones weigh if you need the metal on its own.
Why does every result say to weigh the real piece?
Density tables are theoretical, ring charts disagree by hundredths of a millimetre, and a chain’s fill is a number you typed. Solder, porosity and a rounded edge move the real weight. Weigh the object before you sell it.
How do I weigh jewelry at home?
Use a scale that reads to 0.01 g. A kitchen scale that jumps by 1 g is too coarse for a thin band. Tare a small cup, set the piece in it, and weigh it twice. Stones stay in the reading if you cannot remove them. A jeweler’s pennyweight scale is the better check before a sale.
Is the optional value what a buyer will pay?
No. It multiplies the pure-gold portion by the spot price on the calculator. The checkbox starts on, and turning it off hides the dollar lines. A buyer tests the piece and keeps a margin. A density you typed does not set the purity. The dollar line uses the karat you pick, divided by 24.