Mass and Weight · Unit Converter

Convert Dram (apothecary/troy) to Troy Ounce

Convert drams (apothecary/troy) to troy ounces instantly. 1 dram (apothecary/troy) = 0.125 troy ounce — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Troy Ounce to Dram (apothecary/troy) converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Dr. Ashok Kumar K, Ph.D.
Mass and Weight category 2 min read Published Last reviewed Updated

Units explained

Troy & Apothecary

Dram (apothecary/troy)

What is a dram (apothecary/troy)?

The apothecary (troy) dram equals one-eighth of a troy ounce, about 3.888 grams.

Origin of the dram (apothecary/troy)

From the apothecaries' system rooted in the Greek 'drachma'.

Where it is used

Historical pharmacy and medicine compounding.

When and where it was developed

Part of the apothecaries' system of weights used through the 19th century.

Troy & Apothecary

Troy Ounce

What is a troy ounce?

The troy ounce (ozt) equals about 31.103 grams, one-twelfth of a troy pound.

Origin of the troy ounce

From the Troy system of weights associated with Troyes, France.

Where it is used

The global standard for pricing gold, silver, platinum, and palladium.

When and where it was developed

Established in the medieval Troy system and retained for precious metals.

Dram (apothecary/troy) to Troy Ounce conversion formula

The relationship between drams (apothecary/troy) and troy ounces:

1 dr ap = 0.125 oz t
1 oz t = 8 dr ap

To convert drams (apothecary/troy) to troy ounces, multiply the value in drams (apothecary/troy) by 0.125. To reverse, multiply troy ounces by 8.

How to use this converter

Type a value into the calculator. The result in troy ounces updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Troy Ounce to Dram (apothecary/troy) converter for the reverse direction.

Step-by-step: convert drams (apothecary/troy) to troy ounces

  1. Write down the value in drams (apothecary/troy) (dr ap).
  2. Multiply that value by the factor 0.125.
  3. The product is the equivalent value in troy ounces (oz t).
  4. To reverse, multiply the troy ounce value by 8.

Worked examples

Example 1 — Convert 1 dr ap to oz t:
1 × 0.125 = 0.125 oz t

Example 2 — Convert 100 dr ap to oz t:
100 × 0.125 = 12.5 oz t

Real-world example — Ruler-scale measurements

A 30-dram (apothecary/troy) school ruler converts cleanly to troy ounces — useful when buying a desk accessory from a retailer whose product specs use a different unit.

30 dr ap × 0.125 = 3.75 oz t

Real-world example — Hardware-scale dimensions

A 10-dram (apothecary/troy) fastener or component is about as long as a thumbnail. Mechanics and DIY enthusiasts convert between drams (apothecary/troy) and troy ounces daily when mixing metric and imperial tools.

10 dr ap × 0.125 = 1.25 oz t

Real-world example — Postcard and small-object dimensions

A postcard is about 5 drams (apothecary/troy) wide. Converting to troy ounces is essential for international postal addressing forms that ask for dimensions in different units across countries.

5 dr ap × 0.125 = 0.625 oz t

Dram (apothecary/troy) to Troy Ounce conversion table

Standard reference values for converting drams (apothecary/troy) to troy ounces:

Dram (apothecary/troy) [dr ap]Troy Ounce [oz t]
0.010.00125
0.10.0125
10.125
20.25
30.375
40.5
50.625
101.25
202.5
303.75
405
506.25
10012.5
50062.5
1000125

Frequently asked questions

How many troy ounces is 1 dram (apothecary/troy)?
1 dram (apothecary/troy) equals 0.125 troy ounce.
How do I convert drams (apothecary/troy) to troy ounces?
Multiply the value in drams (apothecary/troy) by 0.125 to get troy ounces.
How do I convert troy ounces back to drams (apothecary/troy)?
Multiply the value in troy ounces by 8, or use the Troy Ounce to Dram (apothecary/troy) converter.
How many troy ounces is 100 drams (apothecary/troy)?
100 drams (apothecary/troy) equals 12.5 troy ounces, because 100 × 0.125 = 12.5.

Convert Dram (apothecary/troy) to other weight units

Show all Dram (apothecary/troy) conversions
Metric / SI (18 units)
Avoirdupois (15 units)
Troy & Apothecary (9 units)
Indian / South Asian (6 units)
Scientific / Atomic (9 units)
Astronomical (4 units)
Biblical / Ancient (14 units)
Force / Engineering (5 units)

Sources & references

Conversion factor (1 dr ap = 0.125 oz t) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.