How many drams are in one carat?

One carat equals approximately 0.1129 avoirdupois drams. Conversely, one dram is about 8.859 carats. The conversion comes from 1 carat being 0.2 grams and 1 dram being approximately 1.7718 grams.

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

The avoirdupois dram (1/16 ounce, about 1.772 g) is used in the common weight system. The apothecary dram (1/8 apothecary ounce, about 3.888 g) was used in pharmacy. They share a name but are different weights, which caused confusion for centuries.

Is the dram still used anywhere today?

The dram is largely obsolete. It survives in some American cooking references for spice quantities and occasionally in ammunition specifications (where powder charges were historically measured in drams). Modern pharmacy has entirely abandoned it in favor of metric units.

Carats to Drams (ct to dr) Converter

1 ct = 0.1129 dr

1 Carat equals 0.1129 Drams (1 ct = 0.1129 dr). Convert Carats to Drams with formula, table, and examples.

One carat equals approximately 0.1129 drams (avoirdupois). The dram is an old English unit of weight equal to 1/16 of an ounce, or about 1.7718 grams. Converting between carats (used for gemstones) and drams (an archaic unit from the apothecary and trading traditions) bridges two measurement systems that evolved for entirely different purposes.

How to Convert Carats to Drams

dr = ct × 0.1128766782

Multiply the value in Carats by 0.1128766782

Take your value in Carats
Multiply by 0.1128766782
Read the result in Drams

Common Carats to Drams Conversions

Carats (ct)	Drams (dr)	Status
1 ct	0.112877 dr
5 ct	0.564383 dr
10 ct	1.128767 dr
25 ct	2.821917 dr
50 ct	5.643834 dr
100 ct	11.287668 dr
250 ct	28.21917 dr
500 ct	56.438339 dr
1,000 ct	112.876678 dr
2,500 ct	282.191696 dr
5,000 ct	564.383391 dr
10,000 ct	1,128.766782 dr

Good to Know About Carats to Drams Conversion

The dram's name comes from the Greek 'drachma,' an ancient coin and weight unit. Through Latin and Old French, it entered English as both a measure of weight and a measure of liquid volume (the fluid dram). The existence of two different drams - avoirdupois and apothecary - caused errors in medicine for centuries, contributing to the global push toward metric units in pharmacy during the 20th century.

Carats to Drams: What You Need to Know

The avoirdupois dram survives mainly in American cooking (some spice measurements) and in historical pharmaceutical references. A typical 1-carat diamond weighs only about 0.11 drams, illustrating how light gemstones are compared to the quantities that drams were designed to measure. You would need nearly 9 one-carat diamonds to weigh a single dram. This conversion occasionally arises in antique appraisals where older records mixed gemstone carats with apothecary drams.

What is a Carat? ct

A carat is a unit of mass equal to exactly 200 milligrams (0.2 grams), used for measuring gemstones and pearls. Adopted internationally in 1907 by the Fourth General Conference on Weights and Measures.

Metric diamond weight gemstone grading pearl measurement

Learn more about Carat →

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 Carats converter.

Carats to Drams FAQ

One carat equals approximately 0.1129 avoirdupois drams. Conversely, one dram is about 8.859 carats. The conversion comes from 1 carat being 0.2 grams and 1 dram being approximately 1.7718 grams.
The avoirdupois dram (1/16 ounce, about 1.772 g) is used in the common weight system. The apothecary dram (1/8 apothecary ounce, about 3.888 g) was used in pharmacy. They share a name but are different weights, which caused confusion for centuries.
The dram is largely obsolete. It survives in some American cooking references for spice quantities and occasionally in ammunition specifications (where powder charges were historically measured in drams). Modern pharmacy has entirely abandoned it in favor of metric units.

Non-Frequently Asked Questions About Carats to Drams

Questions nobody should ask - but someone did.

A 'dram' of Scotch whisky is a colloquial pour, not a precise measurement. In practice, a dram of whisky can be anything from a sip to a generous glass (25 to 70 ml). The weight dram (about 1.77 grams) would only fill a thimble. Scotch enthusiasts would find this amount deeply unsatisfying.
Historically, you might have. Medieval traders sometimes valued goods by weight of precious metal. A 1-carat diamond (0.11 drams) could be traded against its equivalent weight in gold at the going rate. Today, a 1-carat diamond is worth far more than 0.11 drams of gold, because cut diamonds carry craftsmanship and rarity premiums.
At 1.77 grams, a dram is already quite light. Saying someone lacks a dram of sense means they have less than 1.77 grams of intelligence. In carats, that is less than 8.86 carats of brainpower. Either way, it is not a compliment, and the precision of the insult makes it sting more.