Gold Bar Weight
$4,195.60 per troy ounce of gold
$134.89 per gram · $134,892 per kilogram
Gold spot $4,195.60/oz · updated
Quick answer: Gold bars are sold in grams, troy ounces and kilos. A troy ounce is 31.1035 grams, which makes it 9.7 percent heavier than the regular ounce used for food and mail. A 1 oz bar weighs 31.1035 grams, a 10 oz bar weighs 311.035 grams and a kilo bar weighs 1,000 grams, or 32.1507 troy ounces. Weight is what sets the price, because gold is valued per troy ounce at the live gold price, which is $4,195.60 right now.
The size ladder
Here are the common sizes with their weights in the units you will meet and the value of the gold at today's spot price. The values are for pure gold at spot, before a seller's premium. Each size is covered in more detail on its own page, and the gold bar price page gives the same figures with a premium checker.
| Bar size | Grams | Troy ounces | Gold at spot |
|---|---|---|---|
| 1 g | 1 | 0.0322 | $134.89 |
| 5 g | 5 | 0.1608 | $674.46 |
| 10 g | 10 | 0.3215 | $1,348.92 |
| 20 g | 20 | 0.6430 | $2,697.83 |
| 50 g | 50 | 1.6075 | $6,744.58 |
| 100 g | 100 | 3.2151 | $13,489 |
| 1 oz | 31.1035 | 1 | $4,195.60 |
| 10 oz | 311.035 | 10 | $41,956 |
| 1 kg | 1,000 | 32.1507 | $134,892 |
| 400 oz | 12,441.4 | 400 | $1,678,240 |
Read the table from the bottom if you want to see the scale. The 400 oz bar at the foot is the bank vault bar, and it weighs more than twelve kilograms. The bars most people hold are in the upper half.
Notice that the troy ounce column and the gram column do not move together in whole numbers. A 100 g bar is a little over 3.2 troy ounces, and a 50 g bar is a little over 1.6. When you compare a bar sold in grams with a bar sold in ounces, convert both to the same unit first.
Troy ounce versus regular ounce
The word ounce hides two different weights. The regular ounce, formally the avoirdupois ounce, is 28.3495 grams. The troy ounce is 31.1035 grams. The troy ounce is the one used for precious metals, and it is 9.7 percent heavier.
The difference is 31.1035 minus 28.3495, which is 2.754 grams per ounce. That sounds small, and for one ounce it is. It grows with size. Take a kilo: it is 32.1507 troy ounces but about 35.3 regular ounces. If you read the second number as though it were troy ounces, you would think you had gold worth noticeably more than you do.
There is another trap, in the opposite direction. A scale at home, or a postal scale, is usually calibrated in regular ounces and grams. If you weigh a 1 oz gold bar on it and the display says 1.097 ounces, nothing is wrong. That is the same bar, 31.1035 grams, shown in the lighter unit.
So the safe rule is to use grams when you want to compare weights and to use troy ounces when you want to price them. Gold's price is quoted per troy ounce, and the troy ounce is the unit stamped on most 1 oz and 10 oz bars. When a bar is stamped in grams, the stamp is the figure to trust.
For a quick conversion, divide grams by 31.1035 to get troy ounces, or multiply troy ounces by 31.1035 to get grams. For kilos, multiply by 32.1507 to go from kilos to troy ounces.
Why weight sets the price
A gold bar is priced from its weight. The market sets a price for one troy ounce of pure gold, and the value of your bar is the number of troy ounces it contains times that price. Nothing else about the bar enters the spot value. Its shape, size on the table and the design do not change what the metal is worth.
The weight stamped on the bar is the weight of the bar. If the bar is not pure, the pure gold inside is the weight times the fineness. A .9999 bar is almost entirely gold, and a .995 bar contains slightly less. For a quick figure, the value of a bar that weighs 100 g and is marked .9999 is nearly the same as the table's 100 g row.
To value a bar yourself, take the weight in grams and multiply by the spot per gram, $134.89. Or take the weight in troy ounces and multiply by $4,195.60. Either way, write the date down with the result. The guide to how much a gold bar is worth shows the same arithmetic and explains why the price you pay and the price you get back differ.
Weight also decides which premium applies. A small bar carries more of its price in premium, because the packaging and handling cost the same on any size. A large bar spreads those costs. Three size guides take that up one at a time: 1 oz gold bar, then 10 oz gold bar, then 1 kilo gold bar.
Checking a bar's weight
Weight is also one of the checks on whether a bar is what it claims to be. A bar that is stamped 1 oz should weigh 31.1035 grams on a good scale, within the tolerance of the scale. A bar that weighs noticeably less, or is much larger than its stamp suggests, is a reason to stop and ask questions.
A kitchen scale is a rough tool, but it can catch an obvious mismatch. It cannot prove a bar is genuine, because a bar can have the right weight and still be the wrong metal or a plated core. Weight is one signal among several, and the guide on how to tell if a gold bar is real puts it in order with the others, starting with the seller.
Keep the bar in its sealed card or case while you do this where you can. Opening an assay package to weigh a bar can reduce what a later buyer will pay, so weigh the packed bar if you only want a rough figure.
What this can't tell you
This page can't tell you the exact weight of your bar. Bars are made to a tolerance, and the stamp is the figure to trust. It also can't tell you the fineness of a bar that has no mark, and a scale cannot tell you that either.
It can't tell you what a seller will charge. The values here are spot values, and a seller's premium comes on top. And it can't tell you where the price goes next, so the table is a snapshot that refreshes with the live feed.
FAQ
How much does a 1 oz gold bar weigh?
A 1 oz gold bar weighs one troy ounce, which is 31.1035 grams. That is a little more than a regular ounce, which is 28.3495 grams. The weight is stamped on the bar, and a good scale should agree with it within a small tolerance.
How many grams are in a troy ounce?
A troy ounce is 31.1035 grams, as rounded from the exact definition of 31.1034768 grams. To convert grams to troy ounces, divide by 31.1035. To convert troy ounces to grams, multiply. Gold is priced per troy ounce, so this is the conversion that matters.
How heavy is a kilo gold bar?
A kilo gold bar weighs 1,000 grams, which is 32.1507 troy ounces. In regular ounces it is about 35.3. Gold is priced per troy ounce, so a kilo bar is worth just over thirty-two times a 1 oz bar at spot.
Does a heavier bar always cost more per ounce?
The opposite is the usual pattern. The gold is priced the same per ounce at spot, but a bigger bar tends to carry a smaller premium per ounce, since packaging and handling are spread across more metal. Your quote is the only number that settles it.
Keep reading
- gold bar price: the spot value of each size, with a premium checker
- how much a gold bar is worth: what a bar fetches when you buy and when you sell
- 1 kilo gold bar: the kilo size, with its storage points
Data sources: Spot price via api.gold-api.com · COMEX futures (GC=F) via Yahoo Finance. Prices are for informational purposes only and may be delayed. Figures on this page were generated . Gold is quoted in US dollars per troy ounce.