Is 1 oz the same as 1 troy oz?

No, 1 oz (ounce) is not the same as 1 troy oz (troy ounce). While they are both units of weight, there is an important difference between the two.

An ounce is a unit of weight commonly used in the United States and the Imperial system of measurements. It is equal to 28.35 grams. On the other hand, a troy ounce is a unit of weight used specifically for precious metals such as gold, silver, platinum etc. A troy ounce is equal to 31.1034768 grams, which makes it heavier than a regular ounce.

Some key differences between the two:

  • A regular ounce (oz) equals 28.35 grams while a troy ounce (oz t) equals 31.1034768 grams.
  • A troy ounce is about 10% heavier than a regular ounce. 1 oz = 28.35g while 1 oz t = 31.1034768g.
  • Regular ounces are used to measure everyday items. Troy ounces are used specifically for precious metals.
  • There are 16 regular ounces in 1 pound (lb) and only 12 troy ounces in 1 troy pound.

So in summary:

1 oz (regular ounce) ≠ 1 oz t (troy ounce)

They may share the same abbreviation but are distinct units of measurement. Now let’s look at each of them in more detail.

What is a Regular Ounce?

The ounce (abbreviated as oz) is a unit of weight that is commonly used in the United States and Imperial system of measurements. It is equal to 28.35 grams.

Some key facts about the regular ounce:

  • The international avoirdupois ounce is defined as exactly 28.349523125 g.
  • In the avoirdupois system, 16 ounces make up 1 pound.
  • It is used to measure the mass or weight of everyday items such as food produce, postal items, and so on.
  • The ounce is commonly divided into smaller units like 1/2 oz, 1/4 oz, 1/8 oz, etc.
  • Ounce measurements are widely used by cooks for recipe ingredients.

The ounce has been a unit of weight in the English system of measurement since the 1300s. Originally the term referred to 1/12th of a pound. Over time as measurement standards evolved, the ounce was redefined as 1/16th of an avoirdupois pound.

So in summary, the regular ounce we use today equals 28.35 grams and is widely used to measure everyday items, ingredients, and consumer goods in the US and Imperial system.

What is a Troy Ounce?

The troy ounce (abbreviated as oz t) is a unit of weight that is used specifically for measuring precious metals such as gold, silver, platinum, and palladium. It is equal to 31.1034768 grams.

Some key facts about the troy ounce:

  • 12 troy ounces make up one troy pound.
  • The origins of the troy system are unclear but may date back to the Roman empire.
  • It was brought to England in the Middle Ages and adopted as the official system of weighing silver and gold.
  • The troy ounce is commonly used worldwide by precious metals dealers and investors.
  • Precious metals like gold and silver are priced in USD per troy ounce.

Given that precious metals are denser than other materials, the troy system uses heavier weight units. This prevents tiny fractions of ounces being used for bullion trading.

The troy ounce is also sometimes used for measuring gemstones and arrows/bullets. However, its primary use remains for precious metals like gold, silver, platinum, palladium in the finance and jewelry industries.

So in summary, the troy ounce equals 31.1034768 grams and is specifically used for measuring precious metals worldwide.

Ounce vs. Troy Ounce Conversion

Given the differences in their masses, regular ounces and troy ounces cannot be converted equally. Here is how to convert between the two units:

Troy Ounces to Regular Ounces

To convert troy ounces (oz t) to regular ounces (oz):

  • Multiply the number of troy ounces by 0.911458

For example:

  • 1 oz t x 0.911458 = 0.911458 oz
  • 10 oz t x 0.911458 = 9.11458 oz

Regular Ounces to Troy Ounces

To convert regular ounces (oz) to troy ounces (oz t):

  • Multiply the number of regular ounces by 1.09714

For example:

  • 1 oz x 1.09714 = 1.09714 oz t
  • 10 oz x 1.09714 = 10.9714 oz t

So in summary, to convert between the two units:

  • Multiply troy oz by 0.911458 to get regular oz
  • Multiply regular oz by 1.09714 to get troy oz

Common Uses

Regular Ounce Uses

Some common uses of the regular ounce measurement include:

  • Weighing foods, liquids and ingredients for cooking/baking recipes
  • Postal services for calculating mail/package weights and postage
  • Weighing infants in ounces in the US
  • Pricing retail goods like meat, candy, cheese etc. per ounce
  • Athletics for tracking protein powder servings in ounces
  • Industry for tracking inventories of various materials

Essentially, the regular ounce is used for measuring items we encounter in daily life. The fractions of an ounce are convenient for quantifying small amounts like in recipes or for retail trade.

Troy Ounce Uses

The troy ounce is primarily used for:

  • Weighing and pricing precious metals like gold, silver, platinum, palladium
  • Jewelry making and gemstone weighing
  • Minting of coins, medals and bars
  • Finance & investment in commodities, ETFs, futures etc.
  • Precious metal trading and transactions worldwide

The troy system provides a standardized weight unit for precious metal trading globally. Whether buying gold coins or silver bars, checking the weight in troy ounces is standard practice. Financial reports also quote the prices per troy ounce for gold/silver to analyze markets.

So in summary, the troy ounce has a very specialized use case restricted to finance and precious metals trading.


The origins of the troy system can be traced back to the Middle Ages in Europe. Here is a brief history on how it evolved as a unit of weight:

  • The Romans had a unit of weight called the “libra” which was divided into 12 unciae or ounces.
  • This system may have been brought to England during Roman times. The English troy pound was based on the Roman system.
  • During the Middle Ages, the troy system was adopted as the official system for weighing precious metals like silver and gold.
  • The regular avoirdupois system of weights evolved in parallel for weighing everyday items.
  • The use of the troy system became standardized from the 19th century onwards for precious metals.
  • Today the troy ounce is widely used worldwide by finance and precious metals industry.

Some key milestones:

  • 1414 – Henry V made the Troy pound official as the weight standard of precious metals in England.
  • 1824 – British Imperial weights system unified the troy and avoirdupois pounds.
  • 1879 – The International Bureau of Weights and Measures assigned an exact mass to the troy ounce.

So while the ounce has ancient origins, the differentiation between regular ounces for general use and troy ounces for gold/silver became clearly established around the Middle Ages in Europe.

Significance in Finance & Bullion

The troy ounce plays an important role in financial markets and precious metals trading today. Here are some key reasons:

  • Provides a standardized global unit for bullion trading of gold/silver.
  • Allows transparent pricing and reporting in USD per troy ounce.
  • High precision enables trading small differences in weight for large dollar amounts.
  • Commodities like gold/silver are traded in futures contracts priced per troy ounce.
  • ETFs and funds tracking precious metals also track prices per troy ounce.
  • Easy conversion since 1 troy oz of gold is same density anywhere.

Some examples:

  • Gold prices are typically quoted in USD per troy ounce.
  • 1 troy oz American Eagle gold coin has a face value of $50 USD.
  • 1000 oz silver bars are the standard for large bullion transactions.
  • The NYMEX gold futures contract size equals 100 troy ounces.

So in summary, the troy weight system provides a vital standardized global benchmark for precious metal financial transactions. It enables global connectivity between various markets and trading centers.

Differences in Other Units

The differences between regular ounces and troy ounces also extend to their other measurement units:


  • 1 regular avoirdupois pound = 16 oz = 453.59 g
  • 1 troy pound = 12 oz t = 373.24 g


  • 1 regular grain = 64.79891 mg
  • 1 troy grain = 64.79891 mg

So while pounds and grains also differ between the two systems, the grain has the same mass due to being a common unit.

Countries Using Each System

Here are some of the main countries and regions that use each system:

Regular Ounce System

The regular avoirdupois ounce is commonly used in:

  • United States
  • United Kingdom
  • Canada
  • Australia
  • New Zealand

It is a part of the imperial system used in many English-speaking countries. The avoirdupois system with the 16 oz/lb is now standardized across these countries.

Troy Ounce System

The troy ounce is the standard for weighing precious metals worldwide including:

  • United States
  • Canada
  • Australia
  • UK
  • China
  • Japan
  • India
  • Switzerland
  • Global bullion markets

It is the accepted standard among major economies and gold/silver markets. The LBMA in London and COMEX in New York use troy ounces for bullion trading.


In summary:

  • The troy ounce is heavier than the regular ounce with 31.1034768 g vs. 28.349523125 g.
  • Troy ounces are specifically used for weighing precious metals.
  • Regular ounces are used for everyday items.
  • Converting between the two requires a multiplier factor.
  • The troy system was historically adopted for gold/silver weights in Europe.
  • It serves an important role in precious metals finance and trade today.

So while the two ounce units share the same name, they are distinct measurement units with different uses and masses. The troy ounce continues to be vital for bullion trading and financial systems tracking precious metals today.

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