# Pennyweights to Drams (dwt to dr) Source: https://www.unitconvertercalculator.com/weight/pennyweights-to-drams/ **1 dwt = 0.87771428571429 dr** One pennyweight equals approximately 0.878 avoirdupois drams. This conversion bridges two distinct historical weight systems: the troy pennyweight used for precious metals and the avoirdupois dram used for general commerce. Since both units are relatively small, they operate in similar magnitude ranges, making their relationship more intuitive than many cross-system conversions. ## Formula Apply the conversion factor ## Conversion Table | Pennyweights (dwt) | Drams (dr) | |---|---| | 0.5 dwt | 0.43885714285714 dr | | 1 dwt | 0.87771428571429 dr | | 2 dwt | 1.7554285714286 dr | | 5 dwt | 4.3885714285714 dr | | 10 dwt | 8.7771428571429 dr | | 20 dwt | 17.554285714286 dr | | 50 dwt | 43.885714285714 dr | | 100 dwt | 87.771428571429 dr | | 200 dwt | 175.54285714286 dr | | 240 dwt | 210.65142857143 dr | | 500 dwt | 438.85714285714 dr | | 1000 dwt | 877.71428571429 dr | | 5000 dwt | 4388.5714285714 dr | ## Units ### 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. ### Dram (dr) A dram (avoirdupois) is a unit of mass equal to 1/16 of an ounce or 1/256 of a pound (1.7718451953125 grams). Historically used in pharmacy and old cooking recipes. ## Background Historical trade records from colonial America occasionally mixed troy and avoirdupois measurements in the same ledger, particularly when a merchant dealt in both precious metals and general goods. A silversmith who also sold spices might record silver in pennyweights and pepper in drams on adjacent pages. Understanding both units helps researchers interpret these blended commercial records. ## Good to Know The pennyweight and the dram both trace their roots to ancient Mediterranean commerce but arrived in English through different routes. The pennyweight came via Norman French silver trading standards, while the dram traveled from the Greek drachma through Arabic dirham into medieval English apothecary practice. Their parallel existence in English measurement reflects the layered history of trade influence on the British Isles. ## FAQ ### How many avoirdupois drams are in one pennyweight? One pennyweight equals approximately 0.878 avoirdupois drams. The pennyweight (1.555 grams) is slightly lighter than the avoirdupois dram (1.772 grams), so each pennyweight converts to slightly less than one dram. ### Why are pennyweights and drams from different systems? The pennyweight belongs to the troy system developed for precious metals, originating from French trade fairs. The dram belongs to the avoirdupois system used for everyday goods, originating from Italian merchant practices. They evolved independently for different commercial purposes and were never intended to align. ### Is either unit still in regular use? The pennyweight remains active in the North American precious metals and jewelry trade. The avoirdupois dram has largely fallen out of everyday use, though it persists in the ammunition industry through 'dram equivalent' markings on shotgun shells and in some traditional pharmacy contexts. ## Non-Frequently Asked Questions ### If a colonial merchant confused pennyweights and drams, how bad could the mix-up be? Not catastrophically bad, since the units are only about 12 percent apart. Confusing them on a silver transaction would mean overcharging or undercharging by roughly one-eighth, which would upset a customer but not bankrupt either party. Confusing troy ounces and avoirdupois ounces, however, would produce a 10 percent error that could genuinely sour a business relationship. ### Is a pennyweight of gold worth more than a dram of gold? Surprisingly, a dram of gold is worth slightly more, because the avoirdupois dram is heavier (1.772 g versus 1.555 g). The pennyweight contains about 12 percent less gold by mass. Of course, gold is rarely sold in drams, so this is a theoretical victory for the dram that it cannot actually collect. ### Could a time-traveling pharmacist use pennyweights for prescriptions? A 17th-century apothecary would understand pennyweights, since the troy system was standard in medicine before the metric system arrived. They would not, however, appreciate being called a pharmacist, having their practice disrupted by a time traveler, or discovering that their carefully balanced dram weights would eventually be rendered obsolete by milligrams. ## 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 - [Drams to Pennyweights](https://www.unitconvertercalculator.com/weight/drams-to-pennyweights/)