> A troy ounce is exactly 31.1035 g. Since silver is quoted per ounce but bought back per gram, knowing how to convert is essential to estimate an item's met *Source : https://meilleur-rachat-argent.fr/en/guides/troy-ounce-to-gram/* --- ● Guide # Troy ounce and gram: converting to understand the price Published on **06/08/2026** · By **Sébastien Joumel** In brief A troy ounce is exactly **31.1035 g**. Since silver is quoted per ounce but bought back per gram, knowing how to convert is essential to estimate an item's metal value yourself. ## The troy ounce, unit of precious metals The ounce used for gold and silver is the **troy ounce**, not to be confused with the everyday ounce. It equals exactly 31.1035 g. It is the unit in which international markets quote the silver price, generally in dollars per troy ounce. For a seller, this unit can cause confusion because items are weighed in grams. Hence the need to convert. An "one ounce" investment coin thus weighs about 31.1 g. Understanding this equivalence avoids estimation errors. To track the price in the right unit, our guide on [the silver ounce price in euros](https://meilleur-rachat-argent.fr/en/guides/silver-ounce-price-euro/) explains how to read quotes. ## Converting the price into a per-gram figure To move from a per-ounce price to a per-gram price, divide the price by 31.1035. Conversely, multiply a per-gram price by 31.1035 to recover the per-ounce price. This conversion applies to **fine** metal, that is, pure metal. For an item that is not pure silver, you must first calculate the **fine weight**: total weight × fineness. A 100 g item in 925 silver contains 92.5 g of pure silver. You then multiply this fine weight by the day's silver price per gram. The ounce-to-gram conversion is therefore just one step; the fineness remains decisive for knowing the real amount of precious metal. ## A benchmark to estimate, not a firm price Converting lets you obtain an **order of magnitude** of the metal value, useful for judging an offer. But this calculation gives the theoretical metal value, not the buyback amount: the professional then applies their margin, which varies from one buyer to another. Keep the full logic in mind: total weight → fine weight (× fineness) → metal value (× price per gram) → buyback offer (− margin). Mastering the ounce-to-gram conversion puts you in a position to compare proposals on a solid basis. Once your estimate is made, put professionals in competition via our [silver buyback](https://meilleur-rachat-argent.fr/en/silver-buyback/) page to obtain the best rate. ## Frequently asked questions How many grams are in a silver ounce? A troy ounce, the unit of precious metals, equals exactly 31.1035 g. An "one ounce" silver investment coin therefore weighs about 31.1 g, at a fineness of 999 or 9999 thousandths. How do I convert the ounce price into a per-gram price? Simply divide the ounce price by 31.1035 to get the per-gram price of the fine metal. For an item that is not pure, then multiply by the fineness to obtain the value of the real fine weight. ## Read also [ Guide French silver hallmarks: Minerva, crab, complete guide ](https://meilleur-rachat-argent.fr/en/guides/french-silver-hallmarks/)[ Guide Gold-silver ratio: what it says about the right time to sell ](https://meilleur-rachat-argent.fr/en/guides/gold-silver-ratio/)[ Guide How to identify solid silver: hallmarks and tests ](https://meilleur-rachat-argent.fr/en/guides/how-to-identify-solid-silver/) ## Sell at the best price near you Compare the silver buyers in your city. [See the rankings](https://meilleur-rachat-argent.fr/en/silver-buyback/)