How many drams are in one ounce?

Exactly 16 avoirdupois drams make one avoirdupois ounce. This is a defined relationship within the avoirdupois system, not an approximation.

Why 16 drams per ounce?

Medieval English measurement favored powers of 2 for easy subdivision: 16 halves into 8, 4, 2, and 1. This made splitting portions at market stalls practical without complex arithmetic. The same base-16 logic gives us 16 ounces per pound.

Is the dram-ounce relationship the same in all weight systems?

No. The avoirdupois system has 16 drams per ounce. The apothecary system had 8 drams per ounce. This naming collision between different-sized drams in different systems was a major source of pharmaceutical errors before metrication.

Drams to Ounces (dr to oz) Converter

1 dr = 0.0625 oz

1 Dram equals 0.0625 Ounces (1 dr = 0.0625 oz). Convert Drams to Ounces with formula, table, and examples.

One dram equals exactly 1/16 of an ounce, or 0.0625 ounces. This is one of the fundamental relationships within the avoirdupois system: 16 drams make one ounce, just as 16 ounces make one pound. The clean factor of 16 reflects the medieval English preference for powers of two, which made halving and quartering easy at market stalls.

How to Convert Drams to Ounces

oz = dr ÷ 16

Divide the value in Drams by 16

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

Common Drams to Ounces Conversions

Drams (dr)	Ounces (oz)	Status
1 dr	0.0625 oz
2 dr	0.125 oz
4 dr	0.25 oz
8 dr	0.5 oz
10 dr	0.625 oz
16 dr	1 oz
24 dr	1.5 oz
32 dr	2 oz
48 dr	3 oz
64 dr	4 oz
100 dr	6.25 oz
128 dr	8 oz
256 dr	16 oz
500 dr	31.25 oz
1,000 dr	62.5 oz

Good to Know About Drams to Ounces Conversion

The 16-dram ounce is one of the oldest surviving weight relationships in English measurement, traceable to at least the 14th century. The factor of 16 was chosen for its divisibility - it splits evenly into halves, quarters, and eighths, making it ideal for pre-calculator market arithmetic. This practical wisdom of medieval merchants is embedded in every ounce still measured in America today.

Drams to Ounces: What You Need to Know

A standard US fluid medicine cup holds 1 ounce (16 drams) of liquid. An ounce of ground pepper is 16 drams - about 28.35 grams. The dram-to-ounce relationship is the most frequently used dram conversion because the ounce remains common in American food and commerce. When old recipes specify drams, converting to ounces provides immediately useful quantities for modern cooks.

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

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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 →

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

Drams to Ounces FAQ

Exactly 16 avoirdupois drams make one avoirdupois ounce. This is a defined relationship within the avoirdupois system, not an approximation.
Medieval English measurement favored powers of 2 for easy subdivision: 16 halves into 8, 4, 2, and 1. This made splitting portions at market stalls practical without complex arithmetic. The same base-16 logic gives us 16 ounces per pound.
No. The avoirdupois system has 16 drams per ounce. The apothecary system had 8 drams per ounce. This naming collision between different-sized drams in different systems was a major source of pharmaceutical errors before metrication.

Non-Frequently Asked Questions About Drams to Ounces

Questions nobody should ask - but someone did.

Two drams is 0.125 ounces, or one-eighth of an ounce. In teaspoon terms, that is roughly three-quarters of a teaspoon. Most modern bakers would say 'a teaspoon minus a bit' and call it close enough. The dram-to-ounce conversion is exact, but cooking has never been that precise.
Cultural momentum. American measuring cups, nutrition labels, postal rates, and recipe books all use ounces. Switching to grams would require rewriting every recipe, redesigning every measuring cup, and retraining every cook in the country. The ounce persists not because it is better but because it is embedded.
Yes. The avoirdupois system uses 16 at two levels: 16 drams per ounce and 16 ounces per pound. This base-16 structure means a pound is 256 drams (16 x 16). The repeated use of 16 is not coincidental - it was designed for practical halving at every level.