How many pennyweights are in one ounce?

One avoirdupois ounce equals approximately 18.229 pennyweights. Note that this converts from an avoirdupois ounce to troy pennyweights, crossing between two different weight systems. There are exactly 20 pennyweights in one troy ounce.

Why is the pennyweight abbreviated as 'dwt'?

The abbreviation 'dwt' stands for 'denarius weight,' where 'd' comes from the Roman denarius coin (the same origin as the old British penny symbol 'd'). The 'wt' portion simply means weight. This Roman connection reflects how deeply ancient monetary systems influenced weight measurement.

Is the pennyweight still used commercially?

Yes, primarily in the North American jewelry and precious metals trade. Gold buyers, jewelers, and refiners frequently quote prices per pennyweight. It persists because it provides a convenient scale for typical jewelry transactions, where troy ounces are too large and grams feel less intuitive to traditional dealers.

Ounces to Pennyweights (oz to dwt) Converter

1 oz = 18.2292 dwt

1 Ounce equals 18.2292 Pennyweights (1 oz = 18.2292 dwt). Convert Ounces to Pennyweights with formula, table, and examples.

One avoirdupois ounce equals approximately 18.229 pennyweights. The pennyweight (abbreviated dwt) is a unit of troy weight equal to 1/20 of a troy ounce or exactly 1.55517 grams. It remains actively used in the precious metals and jewelry industries for pricing and weighing gold, silver, and platinum.

How to Convert Ounces to Pennyweights

dwt = oz × 18.2291666667

Multiply the value in Ounces by 18.2291666667

Take your value in Ounces
Multiply by 18.2291666667
Read the result in Pennyweights

Common Ounces to Pennyweights Conversions

Ounces (oz)	Pennyweights (dwt)	Status
0.25 oz	4.5573 dwt
0.5 oz	9.1146 dwt
1 oz	18.2292 dwt
2 oz	36.4583 dwt
4 oz	72.9167 dwt
8 oz	145.8333 dwt
10 oz	182.2917 dwt
16 oz	291.6667 dwt
24 oz	437.5 dwt
32 oz	583.3333 dwt
48 oz	875 dwt
64 oz	1,166.6667 dwt
100 oz	1,822.9167 dwt
128 oz	2,333.3333 dwt
256 oz	4,666.6667 dwt

Good to Know About Ounces to Pennyweights Conversion

The pennyweight takes its name from the silver penny of medieval England, which literally weighed one pennyweight (about 1.555 grams). When 240 silver pennies were minted from one troy pound of silver, the pennyweight became the natural subdivision. Although the silver content of the penny changed many times over the centuries, the weight unit preserved its original mass, creating a fossil of medieval monetary policy embedded in modern jewelry scales.

Ounces to Pennyweights: What You Need to Know

Gold buyers at pawn shops and 'cash for gold' establishments typically weigh items in pennyweights and calculate payment accordingly. Jewelers use pennyweights to estimate the metal content of rings, chains, and bracelets. Dental gold is also traded by the pennyweight. The unit's persistence in the jewelry trade makes it a practical conversion for anyone selling or buying precious metals in North America.

What is a Ounce? oz

An imperial and US customary unit of mass equal to approximately 28.35 grams. Commonly used in the US and UK for food and postal weight.

Imperial Us-customary food packaging (US/UK) postal weight cooking (US)

Learn more about Ounce →

What is a Pennyweight? dwt

A pennyweight is a unit of mass equal to 24 grains or 1/20 of a troy ounce (1.55517384 grams). Used in the jewelry trade for weighing precious metals.

Troy jewelry manufacturing precious metal trade goldsmithing

Learn more about Pennyweight →

Going the other way? Use our Pennyweights to Ounces converter.

Ounces to Pennyweights FAQ

One avoirdupois ounce equals approximately 18.229 pennyweights. Note that this converts from an avoirdupois ounce to troy pennyweights, crossing between two different weight systems. There are exactly 20 pennyweights in one troy ounce.
The abbreviation 'dwt' stands for 'denarius weight,' where 'd' comes from the Roman denarius coin (the same origin as the old British penny symbol 'd'). The 'wt' portion simply means weight. This Roman connection reflects how deeply ancient monetary systems influenced weight measurement.
Yes, primarily in the North American jewelry and precious metals trade. Gold buyers, jewelers, and refiners frequently quote prices per pennyweight. It persists because it provides a convenient scale for typical jewelry transactions, where troy ounces are too large and grams feel less intuitive to traditional dealers.

Non-Frequently Asked Questions About Ounces to Pennyweights

Questions nobody should ask - but someone did.

Absolutely not. At current gold prices, one pennyweight of gold (about 1.555 grams) costs roughly 100 to 150 dollars, depending on the market. The name 'pennyweight' is a relic from medieval England when a silver penny actually weighed one pennyweight. Inflation has done the rest.
A modern US penny weighs about 2.5 grams or 1.607 pennyweights. If you found 20 pennies in your couch, they would weigh about 32 pennyweights total. Ironically, the pennies' face value of 20 cents is worth far less than 32 pennyweights of gold, which highlights how far the penny has fallen from its medieval origins.
Jewelers would argue that 20 pennyweights per troy ounce is actually quite elegant. The unit sits perfectly between grams (too small for quick mental pricing) and troy ounces (too large for individual pieces). The confusion arises not from the pennyweight itself but from the existence of two parallel ounce systems that refuse to retire.