How Many Grams In an Ounce of Silver?

Silver is the second most beloved precious metal after gold. Besides its structural properties, it is very respected thanks to the white, elegant color that gives it a note of timelessness. It has a variety of uses, from jewelry making to medicine and electronics.

You can use two primary measurement systems to show this precious metal weight in a particular piece, including a troy ounce and gram. Even though Americans haven’t accepted the metric system, you can quickly learn to calculate how many grams in an ounce of silver. Let’s see.

Metric System History

Many countries developed various measure systems throughout history, but people needed standardized measurements with growing and spreading trade. The need to standardize weight measurement units appeared in the 17th century, and France was one of the first countries to adopt the metric system.

Industrialization, technology development, and the rise of international trading contributed to a unique metric system establishment. Today, this system is known as the International System of Units.

Precious Metals Units of Measurement

The precious metal industry uses several measurements to express the weight. Some of the most common are:

Karat – This unit measures the precious metal purity in an alloy and helps to define its precise weight.

Gram – Gram is a standard weight unit common in most countries. More significant amounts are expressed in kilograms or tons.

Grain – Grain is an ancient unit initially based on the wheat grain weight. 15.43 grains equals 1 gram.

Pennyweight – In medieval England, people used silver pennies whose original weight was equal to 24 grains. One pennyweight is equivalent to 1.555 grams.

Ounce – Avoirdupois (imperial) ounce equals approximately 28.35 g, and you can use it to measure mass, weight, and volume.

Troy ounce – Manufacturers use this old unit to express the gemstones and precious metals weight. Be aware that you can often see the term ‘ounce’ when measuring precious metals, but it is never applied to imperial ounces but troy ones.

In this particular case, it is always about a troy ounce, regardless of the reference used. It can be pretty confusing, but you need to understand the difference since these two measures are not the same. One troy ounce is equal to 31.1 g.

Pound – This old measure comes from Roman libra and equals 0.453 kg. It is a standard unit in the US and the UK nowadays, but no one uses it when measuring precious metals.

Importance of Weight

Determining the price of any precious metal starts by measuring its weight and multiplying that number by a current price per gram or troy ounce.

Troy ounce

A troy ounce is a standard unit of measurement on a precious metals market. It originally comes from France, but it is widely accepted worldwide nowadays. One troy ounce is equal to precisely 31.1034768 g.

In the Middle Ages, Europe was an important trading region. France became the center of international trading, particularly Troyes, the city located in the northeast. Merchants came there from all over the world to trade precious metals in large amounts.

As you can guess, they needed a standardized weight system that helped them do business more efficiently. English King Henry II adopted the troy weight system.

Troy ounce became the official measurement standard for silver and gold in Britain in 1527, and it has remained the standard to this day despite the rise of other units. The US adopted it in 1828.

Troy ounce vs. ounce

It is essential to know that the terms troy ounce and ounce are not the same and understand the difference between them. The scales in groceries stores and supermarkets or the one you keep in the house use so-called avoirdupois ounces, and you use them to measure everyday necessities.

On the other hand, the troy ounce is only for weighing precious metals. Compared to the troy ounce weighing 31.1 g, the avoirdupois ounce weighs slightly less, or only 28.35 g.

1 avoirdupois (imperial) ounce = 437.5 grains = 28.35 g = 18.23 pennyweights

1 troy ounce = 480 grains = 31.1 g = 20 pennyweights

To make things clear, you can compare these two through more familiar pounds.

  • In the avoirdupois system, one pound contains 16 ounces
  • In the troy system, one (troy) pound contains 12 (troy) ounces

As I have already mentioned, you can sometimes see the term ‘ounce’ in both cases, but you need to know that they are two different units used for various purposes. In other words, it is implied that the ounce used to measure gold and silver is actually a troy ounce and not the imperial (avoirdupois) one.

How Many Grams in an Ounce of Silver?

Most people in the US use pennyweights and pounds to measure weight, but most of them are often confused when it comes to converting a troy ounce to grams or vice versa.

So, let’s clear up once and for all how many grams in an ounce of silver. Let me repeat that it is about troy ounces regardless of the abbreviated version of the unit designation.

The first step is to understand that you can use standard weight metric units that include both grams and troy ounces to measure precious metals. You will often see that all large mining companies make silver bars weighing up to 1,000 troy ounces, but it is also common to use 1 kilogram (1,000 grams) that equals 32.15 troy ounces.

When it comes to evaluating silver coins and small bars, grams become a crucial way of measuring. As I have already mentioned, a troy ounce is equal to 31.1034768 g. It can be pretty impractical to use it to measure small bars or coins weighing only a gram or two.

One more vital thing! Nowadays, you can often find coins and medals made of .925 sterling silver that weigh differently. Some of them are precisely one troy ounce heavy, but some can be heavier.

The reason is in the silver purity. You should be aware that such coins always contain 31.103 g of pure silver, but their gross weight can be higher. In other words, only the silver is counted, while added alloys are worthless.

Let’s Do the Math

The best option to understand the whole system is to check your calculation on a particular example. For instance, you can imagine a coin made of .925 sterling silver that measures 7.78 g.

When you want to buy it in the US, you will often find that its weight is calculated in ounces, but you should know that it is actually troy ounce, not the regular one. To avoid any possible fraud, you need to know how to measure your coin correctly. Let’s see.

The first thing to do when you want to buy a silver coin of 7.78 g is to determine its value in troy ounces. Since one troy ounce is equal to 31.1 g, a jeweler will calculate the following way:

7.78 g / 31.1 g = 0.25 troy ounces

However, if you use the avoirdupois system, you will find that one ounce is equal to 28.35 g, and the calculation will be:

7.78 g / 28.35 g = 0.274 ounces

That way, you will get the wrong result and pay more for the same coin. It may seem to you that the difference in weight and price is negligible. However, it can be significant when it comes to large amounts of silver.


Once you learn how to understand the weight of a silver coin or bar, you will also understand how their pricing works. Keep in mind that troy ounces refer only to pure silver.

Therefore, it is crucial to know whether your silver coin is made of pure silver or contains alloys in a lower or higher percentage. You always need to determine the precise silver amount before calculating.

Live metal spot price comparison

Silver price June 29th, 2021 July 2nd, 2021
Per ounce $25.85 $26.22
Per gram $0.83 $0.84
Per kilogram $831.10 $842.99

You can precisely calculate your silver coin or bar by using any of the online charts or calculators available. The only condition is to get a piece made of pure silver. In that case, the calculation is simple.

For instance, if you have a silver bar made of pure silver weighing 5 troy ounces (155.5 g), you will get its current price by multiplying its weight by the price of one troy ounce or gram. At the moment, you will get approximately $130 for your property.

Be aware that all precious metal prices change daily, so you should always check the current price before calculating. Only that way, you will find the best moment for buying and selling.


When checking silver weight before purchasing or selling it, always be sure to understand the used unit of measurement. It is easy to make a mistake, and it will cost you money if you are not careful. You can profit only if you understand the system and use it wisely.

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