How much is a gold bar worth?The short answer: a gold bar’s value depends on four things—its weight, its purity, the current gold price, and the dealer premium. The longer answer is more interesting, because “a gold bar” is not one thing. Bars run from a one-gram sliver worth pocket change relative to bullion to a 400-ounce “gold brick” worth well over a million dollars. Below you’ll find a live calculator, a full size-and-weight chart, and a plain-English breakdown of every major format.
Key takeaways
- Gold bar value = fine gold content (weight × purity) × current gold price, plus any dealer premium.
- Gold is measured in troy ounces: 1 troy oz = 31.1034768 g, and 1 kilogram = 32.1507466 troy oz.
- Common retail sizes run from 1 gram to 1 kilo; the large institutional bar is the ~400 oz London Good Delivery bar (350–430 fine ozt).
- Smaller bars carry higher premiums per ounce; kilo and large cast bars are usually the cheapest way to buy gold per ounce.
- A one-ounce bar always holds one troy ounce of gold, but its physical dimensions vary by mint—there is no universal size.
- Melt value (intrinsic metal) is not the same as the retail purchase price or the dealer buyback price.
How a Gold Bar’s Value Is Calculated
Every credible gold bar calculation follows the same logic: find the bar’s fine gold content, multiply it by the current price per troy ounce to get the melt value, then add an estimated dealer premium if you want a realistic purchase price. Fine gold content is just the bar’s weight multiplied by its purity—a 100-gram bar of .9999 fine gold contains 99.99 grams of pure gold.
The single most common mistake is mixing up units. Gold is priced in troy ounces, not the standard (avoirdupois) ounces used for food and mail. One troy ounce equals 31.1034768 grams, which is about 10% heavier than a standard ounce. That is why a “100-gram” bar is roughly 3.215 troy ounces, not 3.53. The calculator below handles every conversion for you, but the formula is simple enough to follow by hand:
Fine troy ounces = weight in troy ounces × purity. Melt value = fine troy ounces × price per troy ounce. Purchase price = melt value × (1 + premium).
Gold Bar Value Calculator
Enter a bar size, purity, quantity, gold price, and an optional dealer premium to estimate both the melt value (the intrinsic metal content) and a realistic estimated purchase price. All results update instantly. Gold is calculated in troy ounces — one troy ounce equals 31.1034768 grams, which is heavier than a standard (avoirdupois) ounce.
Gold Bar Value Calculator
Estimated value
- Total weight
- 1,000 g · 32.1507 ozt
- Pure gold content
- 32.1475 troy oz
- Reference price / troy oz
- $4,099.20
- Estimated melt value
- $131,779.16
- Estimated dealer premium
- —
- Estimated purchase price
- $131,779.16
- Value per individual bar
- $131,779.16
- Total for 1 bar
- $131,779.16
Estimates are based on the selected weight, purity, market price, and premium. Actual dealer prices, product availability, spreads, taxes, shipping, storage, assay results, and buyback offers may differ. Meridian Gold Group does not guarantee any displayed purchase or resale price.
Gold Bar Sizes & Weight Comparison Chart
The chart below compares the most common gold bar sizes by weight, typical purity, and approximate dimensions. Estimated melt values use the same reference price as the calculator above — currently $4,099.20 per troy ounce — so the two never disagree. Dimensions vary by refinery and product design, so treat them as representative examples rather than universal specifications.
| Common name | Grams | Troy oz | Typical purity | Approx. dimensions | Est. melt value | Common buyer |
|---|---|---|---|---|---|---|
| 1 gram | 1 | 0.0322 | .9999 | ~8 × 15 mm (varies) | $132 | Gifts, entry-level buyers |
| 5 gram | 5 | 0.1608 | .9999 | ~14 × 23 mm (varies) | $659 | First-time stackers |
| 10 gram | 10 | 0.3215 | .9999 | ~19 × 30 mm (varies) | $1,318 | Budget-conscious buyers |
| 1 troy ounce | 31.1 | 1 | .9999 | ~24 × 42 mm minted (varies by mint) | $4,099 | Core North American retail |
| 100 gram | 100 | 3.2151 | .9999 | ~32 × 55 mm (varies) | $13,179 | Mid-tier investors |
| 10 troy ounces | 311.03 | 10 | .9999 | ~40 × 60 mm cast (varies) | $40,992 | Larger private investors |
| 1 kilogram | 1,000 | 32.1507 | .9999 | ~53 × 118 mm cast | $131,792 | Retail–institutional bridge |
| 100 troy ounces | 3,110.35 | 100 | .9995 | Varies by refiner | $409,920 | Institutional / COMEX |
| 400 troy ounces | 12,441.39 | 400 | .995+ | ~272 × 94.5 mm (350–430 ozt range) | $1,639,680 | Central banks, LBMA vaults |
Melt values are gross-weight estimates at the reference price shown and assume the listed purity. A 400 oz “gold brick” is a London Good Delivery bar whose actual content may fall anywhere from 350 to 430 fine troy ounces, so its true value is stamped and certified per bar. See the live gold price for the latest reference figure.
Gold Bar Sizes and What Each One Weighs
Retail bars are sold in clear increments, which makes them the easiest way to understand the market. The World Gold Council defines retail bars as small bars of one kilogram and below, while the wholesale London market centers on the 400-ounce Good Delivery bar. Here is how the major formats break down.
Gram bars: 1 g to 100 g
Small gram bars—1, 5, 10, 20, 50, and 100 grams—are the entry point for most buyers. A one-gram bar weighs one gram; a 100-gram bar holds about 3.215 troy ounces of fine gold. These sizes are common gifts and starter investments because they are affordable, easy to store, and simple to resell piece by piece. The trade-off is a higher premium per ounce, since the cost to fabricate and package a tiny bar is spread over very little metal.
One-ounce and ten-ounce bars
One-ounce gold bars sit at the center of the North American retail market and are the reference format most people picture when they ask how much is a 1 oz gold bar worth. Ten-ounce bars step up for buyers who want more metal in fewer pieces, usually at a lower premium per ounce than one-ounce bars. Both are widely traded in minted and cast formats at .9999 fineness.
One-kilogram bars
A one-kilogram bar contains about 32.15 troy ouncesof fine gold and is the major bridge between retail and institutional ownership. Kilo bars typically publish a footprint in the low-50 mm by roughly 118 mm range, though this varies by refiner. They are prized because they deliver a large amount of gold in a single bar at one of the lowest premiums per ounce—without crossing into the wholesale Good Delivery market.
The 400-ounce Good Delivery bar
The famous large bar associated with central banks and major vaults is the London Good Delivery bar, often shorthanded as a 400-ounce gold bar. But the term is a rough market convention, not a fixed product. Under LBMA technical specifications, a Good Delivery gold bar must contain between 350 and 430 fine troy ounces, meet a minimum fineness of 995.0, and fit within permitted dimensional ranges (an example footprint is roughly 272 × 94.5 mm). That is why the true value of an institutional “gold brick” is stamped and certified per bar rather than fixed at exactly 400 ounces.
Why Large Gold Bars Cost Less Per Ounce
The metal value of a gold bar scales directly with weight, but the purchase price does not, because fabrication, packaging, distribution, and margin are not linear. The World Gold Council and The Royal Mint both explain that smaller bars cost more per ounce—that extra cost is the premium. A one-gram bar is usually the most expensive way to buy a given amount of gold on a per-ounce basis, while kilo bars and large cast bars offer the lowest premium per ounce.
This is exactly why the calculator separates melt value from an estimated purchase price. If you are comparing a stack of one-ounce bars against a single kilo bar for the same total metal, the melt values match—but the smaller bars will cost more once premiums are added. Enter a premium percentage above to see the difference for yourself.
Why Selling Price Differs From Melt Value
Many buyers are surprised to learn that the price to buy a bar and the price to sellit are two different numbers. When you buy, you pay melt value plus a premium. When you sell, a dealer generally pays at or slightly below melt value—the buyback bid. The gap between those two prices is the spread, and it is how dealers make a market.
Several factors affect the real figure on either side of a trade: the product’s recognition and brand, the current spread, assay or authentication for larger or older bars, shipping and insurance, storage, and any applicable taxes. Widely recognized bars from established refiners are typically the easiest to resell at a competitive bid. If you are weighing bars against coins for liquidity, our overview of physical gold coins and the benefits of investing in gold is a useful next read.
Troy Ounces, Fineness, and the Vocabulary of Gold Bars
A quick glossary clears up most confusion when you are comparing gram bars, ounce bars, kilo bars, and Good Delivery bars:
- Troy ounce (ozt) — the unit gold is priced in; 31.1034768 grams.
- Standard (avoirdupois) ounce — the everyday ounce (28.35 g); never used to price gold.
- Gross bar weight — the total weight of the bar as sold.
- Pure gold content — gross weight × purity; the actual gold in the bar.
- Fineness — purity expressed in parts per thousand (e.g., 999.9 = 99.99%).
- Melt value — pure gold content × current price; the intrinsic metal value.
- Dealer premium — the markup over melt value you pay when buying.
- Buyback / bid — what a dealer will pay you when you sell.
With those distinctions in hand, the calculator above becomes a precise tool rather than a rough guess. You can price a single 1-gram bar or a vault of 400-ounce bars, switch between grams, kilograms, and troy ounces, adjust purity for non-standard bars, and layer in a premium to model a realistic buy price. When you are ready to move from research to ownership, Meridian Gold Group can help you compare products, premiums, and storage.