Physical gold & silver
Gold Bar Sizes: 1 oz, 10 oz, 1 Kilo, and 400 oz Bars Compared
Gold bars run from 1 gram, about the weight of a paper clip, up to the 400 oz gold bar that central banks stack in vaults. The sizes most people buy are the 1 oz gold bar, the 10 oz gold bar and the 1 kilo gold bar, and the table below gives the weight of each one plus the arithmetic for what the gold in it is worth.
Sizes at a glance
- A bar's gold value is its weight in troy ounces times the gold price. You pay a premium on top of that.
- The premium per ounce usually shrinks as the bar gets bigger.
- A Good Delivery bar holds 350 to 430 troy ounces of gold at .995 fineness or better, under LBMA rules.
- The 1 oz bar is the easiest size to sell. Very large bars have few buyers outside the wholesale market.
- For an IRA, the tax code's test is fineness, and the bar has to stay with the trustee or custodian.
Common gold bar sizes and what the gold in each is worth
Gold is weighed in troy ounces. One troy ounce is 31.1035 grams, a little heavier than the ounce on a kitchen scale.
The last column uses a gold price of $4,000 an ounce. That's a round number we picked for the arithmetic. It isn't today's price, and a real bar costs more than its gold value because of the premium.
| Bar size | Weight in grams | Troy ounces | Gold value at a made-up $4,000 an ounce |
|---|---|---|---|
| 1 gram | 1 | 0.0322 | About $129 |
| 5 gram | 5 | 0.1608 | About $643 |
| 10 gram | 10 | 0.3215 | About $1,286 |
| 1 oz | 31.10 | 1 | $4,000 |
| 50 gram | 50 | 1.6075 | About $6,430 |
| 100 gram | 100 | 3.2151 | About $12,860 |
| 5 oz | 155.52 | 5 | $20,000 |
| 10 oz | 311.03 | 10 | $40,000 |
| 1 kilo | 1,000 | 32.15 | About $128,600 |
| 100 oz | 3,110 | 100 | $400,000 |
| 400 oz Good Delivery (nominal) | About 12,441 | About 400 | About $1,600,000 |
The formula for gold bar cost
You can redo that last column at any gold price:
- Gold value = troy ounces of gold in the bar × the gold price per troy ounce.
- What you pay = gold value + the dealer's premium, plus any shipping and sales tax.
If the bar is marked in grams, divide the grams by 31.1035 to get troy ounces first. So a 1 kilo gold bar price starts at 32.15 times the gold price, and the premium goes on top. At our made-up $4,000, that's 32.15 × $4,000 = $128,600 before the premium.
Why bigger bars cost less per ounce
Every bar sells for more than the gold in it. The extra is the premium, and it pays for refining, shaping, stamping, packaging, shipping and the dealer's margin.
A lot of that work costs about the same on a 1 gram bar as on a 1 oz bar. Spread it over one gram of gold and it's a big slice of the price. Spread it over a kilo and you barely see it. That's why a stack of ten 1 oz bars costs more than a single 10 oz gold bar, even though the gold is identical.
The trade is flexibility: ten small bars can be sold one at a time, and a 10 oz bar can't. Our comparison of gold bars vs. gold coins has an illustration of how premiums step down by size. Premiums move from week to week, so get a written quote on the day you buy.
Types of gold bars: cast and minted
Bars are made two ways, and you can tell them apart across a room.
- Cast bars are poured. Molten gold goes into a mold and cools there, which leaves rounded edges, a slightly rough surface and small differences between one bar and the next. Bigger bars are almost always cast.
- Minted bars are cut from a rolled strip of gold and then struck like a coin. They have sharp edges, a bright finish and often a design on the back. Most 1 oz and smaller bars are minted. If a dealer stocks both kinds in the same weight, ask for both prices.
The gold is the same either way, so the finish is a matter of taste.
Assay cards and serial numbers
Small minted bars usually come sealed in a plastic card about the size of a credit card. That's the assay card. It states the refiner, the weight and the fineness, and many carry a serial number that matches the one stamped on the bar.
Larger bars have the same details stamped straight into the metal. Write the serial numbers down and keep them with your receipt.
Leave a sealed bar sealed, since some buyers offer less once the card has been opened. And don't treat the card as proof, because counterfeiters copy packaging too. Where you buy matters more, which is the subject of our guide on how to buy gold bars.
What is a Good Delivery gold bar?
"Good Delivery" is the standard for the big bars that trade between banks, refiners and central banks in the London wholesale market. The standard is set by the LBMA, the body that keeps the rules for that market, and the bars are what people mean by a "400 oz gold bar."
The 400 is a nickname. The LBMA's technical specifications set a range instead of one exact weight:
- Gold content: at least 350 fine troy ounces (about 10.9 kilograms) and no more than 430 (about 13.4 kilograms).
- Fineness: at least 995.0 parts per thousand, which is .995 fine.
- Shape: a cast ingot with sloped sides, roughly 250 mm long, 70 mm wide and 35 mm high, with tolerances on each.
- Marks: a serial number, the refiner's stamp, the fineness and, for bars made since January 2019, the year and month of manufacture.
A bar of 400 troy ounces weighs about 12.4 kilograms, or roughly 27 pounds. No two come out the same, so each is weighed and priced on its own fine gold content.
These bars come from refiners on the LBMA's Good Delivery List and sit in wholesale vaults. You won't find one at a coin shop.
And the 100 oz gold bar?
The 100 oz gold bar is a trade size too, and some dealers sell them to individuals. At our made-up $4,000 an ounce, one bar holds $400,000 of gold, so it's a single very large purchase and, later, a single very large sale.
What is the largest gold bar ever made?
The biggest gold bar on record weighs 521.2 kilograms, about 1,149 pounds. The Perth Mint in Western Australia, a government-owned mint, produced it and was awarded the world record title on July 9, 2026. The mint says the bar was refined to 99.999% purity.
That's about 16,760 troy ounces of gold in one piece, as much as about 42 standard 400 oz bars. Guinness World Records lists the previous holder as a 300.12 kilogram bar made by Emirates Minting Factory in Dubai in 2024.
It's a showpiece. The largest gold bar most individual buyers ever handle is the kilo.
Which sizes are easiest to sell?
| Size | Selling it later |
|---|---|
| 1 gram to 10 gram | Easy to sell. Buyers pay for the gold content. |
| 1 oz | The size the gold price is quoted in. Almost any bullion dealer or coin shop will quote one. |
| 5 oz, 50 gram, 100 gram | Bullion dealers buy them. Call ahead at a small shop. |
| 10 oz and 1 kilo | Standard dealer sizes. Each sale is the whole bar, so a small shop may need notice to pay for one. |
| 100 oz and 400 oz | A wholesale-size sale. Expect testing, paperwork and a short list of dealers able to pay for it. |
The refiner matters as much as the size. A bar from a refiner that dealers know gets a quick quote. One from a name nobody recognizes gets tested first, and may get a lower offer. Our guide on how to sell gold covers where to take a bar and how to compare offers.
Some people who want small pieces skip bars and look at the best-known gold bullion coins, which come in 1 oz and fractional sizes.
Which gold bar sizes can go in an IRA?
Size isn't the test. Fineness is. The tax code treats most metal as a collectible that an IRA can't hold, then makes an exception for gold bullion that meets a minimum fineness, which for gold is .995, as long as the IRA's trustee or custodian keeps physical possession of it. The IRS summarizes the exception on its page about collectibles in retirement accounts.
Most retail bars are stamped .999 or .9999, which clears .995, and a Good Delivery bar at 995.0 meets it too. Custodians add their own conditions, such as which refiners and sizes they accept. So the working rule is short: have the custodian confirm the exact bar before any money moves. Our list of IRA-approved gold goes through coins and bars one by one.
A bar you already keep at home can't be moved into an IRA, and an IRA bar can't come home with you without counting as a distribution. See a tax professional before you act on either rule.
Picking a size
Three questions settle most of it. How much are you putting into gold in total? How small a piece might you want to sell someday? And where will the bars live? A kilo takes almost no room, but it's a lot of value sitting in one object, and our guide to storing physical gold and silver covers what that means for a safe, a bank box or a depository.
Whatever the size, a bar's value follows the gold price. This page is education, not personal advice.
Common questions
How much does a 1 oz gold bar cost?
The gold price for one troy ounce plus the dealer's premium, and any shipping or sales tax. Check the gold price on the day, then compare two or three written quotes to see what the premium really is.
How much is a 1 kilo gold bar worth?
A kilo is 32.15 troy ounces, so multiply the gold price per ounce by 32.15. At a made-up $4,000 an ounce that's $128,600 of gold. A dealer sells it for somewhat more than that and buys it back for somewhat less.
How heavy is a 400 oz gold bar?
About 12.4 kilograms, or roughly 27 pounds, if it's exactly 400 troy ounces. Under LBMA rules a Good Delivery gold bar can hold anywhere from 350 to 430 fine troy ounces.
What is the biggest gold bar in the world?
A 521.2 kilogram bar produced by the Perth Mint in Australia, which received the world record title on July 9, 2026. The earlier record was a 300.12 kilogram bar made in Dubai in 2024.
Can an individual buy a Good Delivery gold bar?
It's rare. These bars trade between banks, refiners and central banks and stay in approved vaults. For individuals, the 1 oz, 10 oz and 1 kilo sizes are the ones dealers stock.
We base our guides on primary sources such as the IRS, the Department of Labor, and federal regulators. Read our editorial policy. Spot an error? Tell us.
