How many grains are in one troy ounce?

One troy ounce contains exactly 480 grains. This is a clean whole number, unlike the 437.5 grains in an avoirdupois ounce.

Why is the troy ounce exactly 480 grains?

The troy system defines 1 troy ounce as 20 pennyweights of 24 grains each: 20 x 24 = 480. This structure descends from medieval French bullion trading standards, possibly originating in the city of Troyes.

Is the grain-to-troy-ounce conversion still used professionally?

Yes. Precious metals assayers, refiners, and some jewelers use both grains and troy ounces in their work. The 480:1 ratio is part of the professional vocabulary of the gold and silver industry.

Grains to Troy Ounces (gr to oz t) Converter

1 gr = 0.0021 oz t

1 Grain equals 0.0021 Troy Ounces (1 gr = 0.0021 oz t). Convert Grains to Troy Ounces with formula, table, and examples.

One grain equals exactly 1/480 of a troy ounce, or approximately 0.002083 troy ounces. There are exactly 480 grains in one troy ounce - a clean, elegant number compared to the 437.5 grains in an avoirdupois ounce. This conversion is essential in precious metals assaying, where analytical samples may be weighed in grains and results reported in troy ounces for pricing purposes.

How to Convert Grains to Troy Ounces

oz t = gr ÷ 480

Divide the value in Grains by 480

Take your value in Grains
Divide by 480
Read the result in Troy Ounces

Common Grains to Troy Ounces Conversions

Grains (gr)	Troy Ounces (oz t)	Status
1 gr	0.00208333 oz t
5 gr	0.01041667 oz t
10 gr	0.02083333 oz t
20 gr	0.04166667 oz t
24 gr	0.05 oz t
48 gr	0.1 oz t
50 gr	0.10416667 oz t
100 gr	0.20833333 oz t
200 gr	0.41666667 oz t
240 gr	0.5 oz t
480 gr	1 oz t
500 gr	1.04166667 oz t
960 gr	2 oz t
1,000 gr	2.08333333 oz t
5,000 gr	10.41666667 oz t
7,000 gr	14.58333333 oz t

Good to Know About Grains to Troy Ounces Conversion

The grain is remarkable for being the only unit identical across all three traditional English weight systems (troy, avoirdupois, and apothecary). This universality made it the natural foundation for the entire English measurement tradition. While ounces and pounds changed definition depending on whether you were weighing gold, groceries, or medicine, the grain remained constant: always 64.80 milligrams, everywhere, for everyone.

Grains to Troy Ounces: What You Need to Know

A gold assayer testing a sample of 10 grains (0.648 grams) can determine the gold content and express it in troy ounces by dividing by 480. At gold prices of roughly 2,000 dollars per troy ounce, each grain of pure gold is worth about 4.17 dollars. The grain-to-troy-ounce conversion directly connects laboratory measurement to market pricing in the precious metals industry.

What is a Grain? gr

A grain is a unit of mass equal to exactly 64.79891 milligrams. It is the same in the avoirdupois, troy, and apothecaries' systems, derived from the 1959 international agreement defining the pound as exactly 0.45359237 kilograms.

Imperial Troy Apothecaries ammunition weight bullet measurement historical pharmacy

Learn more about Grain →

What is a Troy Ounce? oz t

A troy ounce is a unit of mass used for precious metals such as gold, silver, and platinum. It equals exactly 31.1034768 grams, about 10% heavier than the common avoirdupois ounce.

Troy gold trading silver pricing platinum markets

Learn more about Troy Ounce →

Going the other way? Use our Troy Ounces to Grains converter.

Grains to Troy Ounces FAQ

One troy ounce contains exactly 480 grains. This is a clean whole number, unlike the 437.5 grains in an avoirdupois ounce.
The troy system defines 1 troy ounce as 20 pennyweights of 24 grains each: 20 x 24 = 480. This structure descends from medieval French bullion trading standards, possibly originating in the city of Troyes.
Yes. Precious metals assayers, refiners, and some jewelers use both grains and troy ounces in their work. The 480:1 ratio is part of the professional vocabulary of the gold and silver industry.

Non-Frequently Asked Questions About Grains to Troy Ounces

Questions nobody should ask - but someone did.

480 divides evenly by 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 20, 24, 30, 32, 40, 48, 60, 80, 96, 120, 160, 240, and 480. This exceptional divisibility made it ideal for the fractional calculations that precious metals trading requires. 437.5, by contrast, is awkward - it has a 0.5 that makes mental arithmetic harder.
At mid-2020s gold prices of roughly 2,000 dollars per troy ounce, one grain of pure gold (1/480 troy ounce) is worth about 4.17 dollars. That is enough to buy a cup of coffee but not lunch. Gold prospectors who find single grains of gold in streams are finding coffee money, not retirement funds.
A typical gold wedding band weighs 3 to 8 grams, or roughly 46 to 123 grains. A 5-gram 14-karat ring contains about 2.92 grams (45.0 grains) of pure gold - worth roughly 188 dollars at current prices. The grain scale makes the gold content of everyday jewelry feel tangible.