Standard Fort Knox Gold Bar Weight
A standard gold bar stored at Fort Knox follows the international Good Delivery standard, which specifies a weight of 400 troy ounces, equivalent to 27.4 pounds or 12.4 kilograms. This is the benchmark size used by the United States Bullion Depository and most major global vaults for institutional gold holdings. The bar's precise weight is tightly controlled to ensure purity and authenticity during audits and transfers. For context on how this compares to other bullion products, see the specifications published by the London Bullion Market Association LBMA standards.
Weight Tolerance and Purity
Under LBMA rules, a 400-ounce gold bar is allowed a small tolerance in weight, typically up to 0.1 percent, meaning the actual weight can vary slightly around the 400-ounce mark. The gold content is required to be at least 99.5 percent pure, and bars are stamped with a serial number, refiner name, and fineness mark. Fort Knox bars are held to the same standards as those traded on the global market, ensuring they remain interchangeable with other institutional-grade gold. The United States Mint produces and assays gold bars that meet these criteria, as detailed in its official bullion programs US Mint bullion.
Physical Dimensions and Appearance
A standard 400-ounce gold bar measures roughly 7 inches by 3.625 inches by 1.75 inches, or about 178 millimeters by 92 millimeters by 44 millimeters. The exact dimensions can vary slightly depending on the manufacturer, but the volume is designed to hold exactly 400 troy ounces of gold at the required purity. These bars have a distinctive rectangular shape with rounded edges and are typically stamped with the issuing refinery's logo, weight, and purity level. Major refiners such as PAMP Suisse and Perth Mint produce bars to these specifications, which are widely recognized in global bullion markets Perth Mint gold bars.
Bar Construction and Security Features
Fort Knox gold bars are produced using refined gold that meets strict purity requirements, and they are cast or minted under controlled conditions to minimize the risk of counterfeiting. Each bar carries a unique serial number and is accompanied by assay certificates that verify its weight and fineness. The United States Bullion Depository at Fort Knox stores these bars under high-security conditions, with access limited to authorized personnel and regular independent audits. For an overview of how the depository operates, see the historical and security details provided by the U.S. Treasury U.S. Treasury.
Market Value and Comparison to Other Gold Bars
The market value of a Fort Knox gold bar is determined by its weight, purity, and the current spot price of gold, with a standard 400-ounce bar representing a significant investment unit. As of the latest available data, a single 400-ounce bar is worth hundreds of thousands of dollars, with the exact figure fluctuating daily based on global gold prices. Smaller bars, such as 1-ounce and 10-ounce sizes, are also traded but are less common in institutional vaults like Fort Knox. The London Bullion Market Association and other bodies track these prices in real time, providing a transparent benchmark for traders and investors LBMA gold price.
Role of Fort Knox in the Global Gold Market
Fort Knox holds a large portion of the United States' official gold reserves, and the 400-ounce bars stored there form the backbone of the country's strategic gold holdings. The depository