# Ounces to Pennyweights (oz to dwt) Source: https://www.unitconvertercalculator.com/weight/ounces-to-pennyweights/ **1 oz = 18.229166666667 dwt** 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. ## Formula Apply the conversion factor ## Conversion Table | Ounces (oz) | Pennyweights (dwt) | |---|---| | 0.25 oz | 4.5572916666667 dwt | | 0.5 oz | 9.1145833333333 dwt | | 1 oz | 18.229166666667 dwt | | 2 oz | 36.458333333333 dwt | | 4 oz | 72.916666666667 dwt | | 8 oz | 145.83333333333 dwt | | 10 oz | 182.29166666667 dwt | | 16 oz | 291.66666666667 dwt | | 24 oz | 437.5 dwt | | 32 oz | 583.33333333333 dwt | | 48 oz | 875 dwt | | 64 oz | 1166.6666666667 dwt | | 100 oz | 1822.9166666667 dwt | | 128 oz | 2333.3333333333 dwt | | 256 oz | 4666.6666666667 dwt | ## Units ### 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. ### 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. ## Background 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. ## Good to Know 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. ## FAQ ### 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. ## Non-Frequently Asked Questions ### Does a pennyweight of gold cost a penny? 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. ### If I collected all the pennies in my couch cushions, how many pennyweights would they weigh? 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. ### Why do jewelers use such a confusing unit? 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. ## Related Articles - [Why We Measure: The Deepest Urge in Human Civilisation](https://www.unitconvertercalculator.com/blog/why-we-measure) - [The Map Is Not the Territory: Why Every Measurement Is Wrong](https://www.unitconvertercalculator.com/blog/the-map-is-not-the-territory) - [Zero: The Most Dangerous Number in Measurement](https://www.unitconvertercalculator.com/blog/zero-the-most-dangerous-number-in-measurement) - [The Kilogram Problem: The Object That Was Its Own Definition](https://www.unitconvertercalculator.com/blog/the-kilogram-problem) - [The Body as a Ruler: Every Measurement Unit That Came From Us](https://www.unitconvertercalculator.com/blog/the-body-as-a-ruler) - [Why Your Recipe Is Lying to You: The Chaos of Cooking Measurements](https://www.unitconvertercalculator.com/blog/why-recipe-measurements-are-unreliable) - [15 Obscure Measurement Units You've Never Heard Of (But Still Need)](https://www.unitconvertercalculator.com/blog/obscure-measurement-units-guide) - [When Measurements Go Wrong - Disasters, Blunders and Happy Accidents](https://www.unitconvertercalculator.com/blog/when-measurements-go-wrong) - [The Surprising Stories Behind Everyday Units of Measurement](https://www.unitconvertercalculator.com/blog/stories-behind-measurement-units) - [Metric vs. Imperial - The Complete Guide to the World's Two Measurement Systems](https://www.unitconvertercalculator.com/blog/metric-vs-imperial-complete-guide) - [Understanding Weight Units - Kilograms, Pounds, Stones & Ounces](https://www.unitconvertercalculator.com/blog/understanding-weight-units) - [Complete Baking Measurement Guide - Cups, Grams, Ounces](https://www.unitconvertercalculator.com/blog/baking-measurement-guide) ## See Also - [Pennyweights to Ounces](https://www.unitconvertercalculator.com/weight/pennyweights-to-ounces/)