How many drams are in one ounce?

There are exactly 16 avoirdupois drams in one avoirdupois ounce. This is a clean ratio with no rounding needed, making conversion between the two units simple multiplication or division by 16.

What is the difference between an avoirdupois dram and an apothecary dram?

An avoirdupois dram weighs approximately 1.772 grams, while an apothecary dram (also called a drachm) weighs about 3.888 grams. The apothecary dram is divided into 3 scruples or 60 grains, whereas the avoirdupois dram contains about 27.34 grains. Context determines which dram is intended.

Why are shotgun shells labeled in dram equivalents?

Early shotgun shells used black powder measured in drams to specify their charge. When smokeless powder replaced black powder, manufacturers kept the 'dram equivalent' label to indicate the velocity a shell would produce compared to the old black powder standard, even though the actual smokeless powder charge is much lighter.

Ounces to Drams (oz to dr) Converter

1 oz = 16 dr

1 Ounce equals 16 Drams (1 oz = 16 dr). Convert Ounces to Drams with formula, table, and examples.

One avoirdupois ounce equals exactly 16 drams. The dram (also spelled drachm) is one of the oldest surviving weight units in the imperial system, subdividing the ounce into 16 equal parts. This clean ratio makes ounce-to-dram conversion straightforward mental arithmetic.

How to Convert Ounces to Drams

dr = oz × 16

Multiply the value in Ounces by 16

Take your value in Ounces
Multiply by 16
Read the result in Drams

Common Ounces to Drams Conversions

Ounces (oz)	Drams (dr)	Status
0.25 oz	4 dr
0.5 oz	8 dr
1 oz	16 dr
2 oz	32 dr
3 oz	48 dr
4 oz	64 dr
6 oz	96 dr
8 oz	128 dr
10 oz	160 dr
12 oz	192 dr
16 oz	256 dr
24 oz	384 dr
32 oz	512 dr
48 oz	768 dr
64 oz	1,024 dr
100 oz	1,600 dr
128 oz	2,048 dr
256 oz	4,096 dr

Good to Know About Ounces to Drams Conversion

The dram descends from the ancient Greek 'drachma,' which served simultaneously as a unit of weight and a coin denomination. In ancient Athens, one drachma of silver was a day's wage for a skilled laborer. The weight meaning traveled through Arabic 'dirham' and medieval Latin before arriving in English as the dram, while the monetary meaning lives on in the Greek drachma currency that preceded the euro.

Ounces to Drams: What You Need to Know

Pharmacists historically measured medications in drams using apothecary weights, and some older American pharmacy references still list dosages this way. In the ammunition industry, powder charges for shotgun shells are frequently specified in drams or 'dram equivalents,' a practice that persists on modern shell boxes even though the actual propellant is measured differently. Perfume formulation also occasionally references the dram as a small liquid measure.

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 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.

Imperial historical pharmacy old recipes whisky measurement

Learn more about Dram →

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

Ounces to Drams FAQ

There are exactly 16 avoirdupois drams in one avoirdupois ounce. This is a clean ratio with no rounding needed, making conversion between the two units simple multiplication or division by 16.
An avoirdupois dram weighs approximately 1.772 grams, while an apothecary dram (also called a drachm) weighs about 3.888 grams. The apothecary dram is divided into 3 scruples or 60 grains, whereas the avoirdupois dram contains about 27.34 grains. Context determines which dram is intended.
Early shotgun shells used black powder measured in drams to specify their charge. When smokeless powder replaced black powder, manufacturers kept the 'dram equivalent' label to indicate the velocity a shell would produce compared to the old black powder standard, even though the actual smokeless powder charge is much lighter.

Non-Frequently Asked Questions About Ounces to Drams

Questions nobody should ask - but someone did.

They share a name and a distant ancestor, but today they measure different things. A 'dram' of whisky is an informal Scottish pour with no fixed volume, ranging from a polite splash to a generous glug depending on the host's mood. A weight dram is precisely 1.772 grams. The Scots have wisely chosen not to standardize their hospitality.
Mathematically, yes. Sixteen drams of anything equal one ounce, including hypothetical drama. A typical reality television episode would weigh in at several pounds of drama, or roughly 1,000+ drams per episode. Thankfully, drama remains weightless outside of metaphor.
Pirates generally used pieces of eight, doubloons, and other coins rather than weighing loose gold in drams. A dram of gold would be worth only a few dollars at current prices, making it a rather disappointing pirate haul. Most self-respecting buccaneers aimed for troy ounces at minimum.