Gold Bar Sizes in Australia: Weights, Prices and Premiums

Walk into any bullion dealer in Sydney or Perth and you will see gold bars that range from the size of a fingernail to a brick you need two hands to hold. Most first-time buyers pick a size by budget alone. That works, but it can cost you more than you think.

In this guide, we explain the common gold bar sizes sold in Australia, how much each one weighs in grams and troy ounces, and what each size really cost on 11 November 2026 using our own gold bar price comparison. You will also see how the premium over spot changes with size, and how to choose the bar that suits your plan.

What Gold Bar Sizes Can You Buy in Australia?

A gold bar is a piece of refined gold, usually 99.99% pure, stamped with its weight, fineness and the name of the refiner. Australian dealers sell bars in both metric and imperial weights, because the local market grew up with grams while the global market still prices gold per troy ounce.

Here are the sizes you will meet most often:

• small bars: 1 g, 2 g, 5 g and 10 g,
• mid-size bars: 20 g, 1 oz, 50 g and 100 g,
• large bars: 10 oz, 250 g, 500 g and 1 kg,
• wholesale bars: the London Good Delivery bar of about 400 troy ounces, which private buyers rarely hold.

A troy ounce is 31.1035 grams. It is a little heavier than the ordinary ounce used for food, so a “1 oz” gold bar weighs just over 31 grams.

Gold bar weights in grams and ounces

The table below converts each common size and shows what the gold inside was worth at the spot price on 11 November 2026, when one troy ounce of gold cost A$5,871.94.

Want to check the gold value of any other weight? Our gold price per gram and gold price per kilogram charts update every day.

How Heavy Is a Gold Bar?

It depends on which bar you mean. When people picture “a gold bar”, they often think of the large bars stacked in central bank vaults. Those are London Good Delivery bars. According to the London Bullion Market Association, a Good Delivery gold bar contains approximately 400 troy ounces, which is roughly 12.4 kg.

These bars trade between banks and large institutions in the wholesale market. They sit behind the global spot price, but you will almost never buy one at a retail dealer. Our glossary entry on LBMA Good Delivery explains how refiners get on the list.

For a private buyer in Australia, the heaviest bar on a dealer’s shelf is usually 1 kg. It weighs about the same as a litre of water, yet it is small enough to fit in your palm, because gold is very dense.

Standard gold bar weight for retail buyers

There is no single standard size for private investors. Two sizes stand out in our price comparison, though: 1 oz and 1 kg. The 1 oz bar matches the way gold is priced worldwide. The 1 kg bar is the cheapest way to hold a lot of gold in one piece.

Minted Bars vs Cast Bars

Before you compare sizes, it helps to know that bars are made in two ways. The method affects the look of the bar and, often, the price.

• Minted bars: cut from a flat strip of gold and struck with a die, like a coin. They have sharp edges, a polished finish and often a design on the front. Most small bars from 1 g to 20 g are minted.
• Cast bars: made by pouring molten gold into a mould. They have softer edges and a rougher surface, and they need less work to produce. Larger bars, such as 250 g and 1 kg, are usually cast.

Minted bars usually come sealed in a card with a serial number. Cast bars are often sold loose or in a simple bag. Does that matter for you? Only a little. Both types are the same pure gold, and the weight and fineness stamped on the bar are what a buyer checks when you sell.

The Perth Mint, owned by the Government of Western Australia, makes both kinds. In our data on 11 November 2026, its Kangaroo minted bars covered 1 g, 5 g and 20 g, while its 1 oz bar was cast.

Gold Bar Prices by Size: Our Data

The premium over spot is the extra you pay above the value of the gold itself. It covers refining, minting, packaging, the dealer’s costs and margin. The formula is simple:

• Premium % = (price of the bar − spot value of its gold) ÷ spot value × 100
• Example, 1 g bar on 11 November 2026: (A$234.85 − A$188.79) ÷ A$188.79 × 100 = 24.4%

To make the comparison fair, the table below uses bars from a single dealer, Australian Bullion Company, all checked on the same day. We add the Perth Mint’s own online prices where it sells the same size.

What jumps out? The 1 g bar costs A$234.85 per gram, while the 1 kg bar costs A$193.16 to A$193.33 per gram. That is a gap of more than A$41 on every gram of gold.

Why the 250 g bar was not the cheapest

You might expect the premium to fall smoothly as bars get bigger. It did not. The 250 g bar carried a premium of 4.4%, higher than the 1 oz bar at 3.6% and almost the same as the 20 g bar.

Why would that happen? Premiums depend on demand and stock for each product, not only on weight. A popular size that a dealer sells in volume can be priced tighter than a less common size. That is why it pays to compare each size on the day you buy, rather than assume the largest bar you can afford is always the best deal.

What about divisible CombiBars?

A CombiBar is a thin bar scored into 1 g pieces that you can snap apart. It sounds like the best of both worlds: one purchase, many small units. The price says otherwise. On 11 November 2026, KJC Gold & Silver Bullion listed Valcambi CombiBars at these premiums:

• 20 g CombiBar (20 × 1 g): A$4,329.22, about 14.7% above spot,
• 50 g CombiBar (50 × 1 g): A$10,509.59, about 11.3% above spot,
• 100 g CombiBar (100 × 1 g): A$20,987.04, about 11.2% above spot,
• 1 oz CombiBar (10 × 1/10 oz): A$6,612.85, about 12.6% above spot.

That is two to three times the premium of a solid bar of the same weight. A CombiBar can make sense if you value the option to break off small pieces, but you pay well for that option.

What 100 Grams of Gold Costs in Different Bar Sizes

So how much does size matter in real dollars? Let’s say you want to own 100 grams of gold. The gold itself was worth A$18,878.73 at spot on 11 November 2026. Here is what you would have paid, depending on how you built that 100 grams:

The same 100 grams of gold cost A$3,700 more as 1 g bars than as 20 g bars. That money is gone the day you buy. When you sell, a dealer pays you for the gold, and it is rare to get the full small-bar premium back.

Read also: Gold Premium Over Spot in Australia: What You Really Pay

Delivery Costs: The Hidden Size Penalty

Dealer prices are often shown before postage. A flat delivery fee barely matters on a 1 kg bar, but it can wreck the maths on a small one. The Perth Mint’s online shop showed these delivery charges in our data on 11 November 2026:

Delivery lifted the premium on the 1 g bar from 24.4% to 35.1%. On the 1 oz bar, it added less than 1.5 points. If you live near a dealer, collecting in person can remove this cost, and you can buy several small bars in one order to spread the fee.

Not sure where to start? Our guide to the cheapest way to buy gold in Australia compares the main routes.

Large Bars Mean Large Price Swings

A big bar has a low premium, but it also puts a lot of money into one object. Every move in the gold price hits the whole bar at once. The chart shows what the gold in a 1 kg bar was worth in AUD over the past year.

At the daily high in our data, on 29 January 2026, gold reached A$7,736.89 per ounce. A 1 kg bar was then worth about A$248,746 at spot. By 11 November 2026, the same bar was worth A$188,787.25, close to A$60,000 less. Over the full year from 11 November 2025, its spot value fell 7.1%.

The percentage move is the same for a 1 g bar and a 1 kg bar. What changes is the amount at stake, and how flexible you are when you need cash.

Which Gold Bar Size Should You Buy?

There is no single best size. The right bar balances three things: the premium you pay, the amount you can afford, and how easily you can sell part of your holding later. Here is a simple guide:

Choose small bars if:

• you want to buy a little gold each month and cannot wait to save for a larger bar,
• you want a gift that carries real gold value,
• you accept paying a higher price per gram for that flexibility.

Choose 1 oz to 1 kg bars if:

• you want as much gold as possible for your money,
• you plan to hold for years and do not expect to sell small parts,
• you have safe storage, at home or in a vault.

A mixed approach works for many buyers

Many investors split their holding across sizes. For example, the core of a holding sits in 1 oz or larger bars, with a few 5 g or 10 g bars on top. If you ever need a small amount of cash, you sell a small bar and leave the rest alone.

Prefer coins? Australian Kangaroo gold coins come in weights including 1/10 oz, 1/4 oz, 1/2 oz and 1 oz, and Australian dealers trade them widely. Compare them in our guide to the best gold coins to buy in Australia.

Is There GST on Gold Bars in Australia?

No, not on investment gold. Under GST law, gold of at least 99.5% fineness in an investment form, such as a bar from a recognised refiner, counts as precious metal. The ATO explains the rules in its ruling on precious metals (GSTR 2003/10). A dealer’s sale of investment gold to you carries no GST, whatever the size of the bar.

So a 1 g bar and a 1 kg bar are taxed the same way when you buy. The size difference you pay comes from the premium, not from tax. Gold jewellery is different and does attract GST. Our glossary entry on GST on gold covers the details, and the fineness entry explains how purity is measured. For your own situation, check with the ATO or a registered tax agent.

Storing and Selling Bars of Different Sizes

Size affects what happens after you buy, too. A few practical points:

• small bars in sealed cards should stay sealed, because a damaged card can make a dealer look more closely before buying,
• a 1 kg bar is compact, so storage space is rarely the problem, but insurance and safe limits may be,
• when you sell, a dealer usually pays a price linked to spot, and the gap between the buy and sell price is called the bid-ask spread,
• keep any certificate or receipt that came with a large bar, as it helps the buyer confirm what you are selling.

For more on keeping gold safe at home or in a vault, read our guide on the proper way to store gold.

Summary: Gold Bar Sizes in Australia

Compare Gold Bar Prices Before You Buy

The premium on each size changes from day to day and from dealer to dealer. That is why we track Australian dealer prices daily and show them side by side, so you can see which size gives you the most gold for your money before you buy.

Start with the sizes that fit your budget: 1 g gold bars, 5 g gold bars, 20 g gold bars, 1 oz gold bars, 100 g gold bars and 1 kg gold bars. You can also browse our list of Australian bullion dealers and follow the gold price chart in AUD.

This article is for information only and is not financial or tax advice.