Mass and Weight · Unit Converter

Convert Pennyweight to Troy Ounce

Convert pennyweights to troy ounces instantly. 1 pennyweight = 0.0499999987 troy ounce — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Troy Ounce to Pennyweight 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

Pennyweight

What is a pennyweight?

The pennyweight (dwt) equals one-twentieth of a troy ounce, 24 grains (about 1.555 g).

Origin of the pennyweight

From the mass of a medieval English silver penny; symbol dwt from 'denarius weight'.

Where it is used

Jewelry making and precious-metal scrap valuation in the US.

When and where it was developed

Derived from the medieval English coinage system.

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.

Pennyweight to Troy Ounce conversion formula

The relationship between pennyweights and troy ounces:

1 dwt = 0.0499999987 oz t
1 oz t = 20.0000005144 dwt

To convert pennyweights to troy ounces, multiply the value in pennyweights by 0.0499999987. To reverse, multiply troy ounces by 20.0000005144.

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 Pennyweight converter for the reverse direction.

Step-by-step: convert pennyweights to troy ounces

  1. Write down the value in pennyweights (dwt).
  2. Multiply that value by the factor 0.0499999987.
  3. The product is the equivalent value in troy ounces (oz t).
  4. To reverse, multiply the troy ounce value by 20.0000005144.

Worked examples

Example 1 — Convert 1 dwt to oz t:
1 × 0.0499999987 = 0.0499999987 oz t

Example 2 — Convert 100 dwt to oz t:
100 × 0.0499999987 = 4.9999998714 oz t

Real-world example — Postcard and small-object dimensions

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

5 dwt × 0.0499999987 = 0.2499999936 oz t

Real-world example — Ruler-scale measurements

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

30 dwt × 0.0499999987 = 1.4999999614 oz t

Real-world example — Hardware-scale dimensions

A 10-pennyweight fastener or component is about as long as a thumbnail. Mechanics and DIY enthusiasts convert between pennyweights and troy ounces daily when mixing metric and imperial tools.

10 dwt × 0.0499999987 = 0.4999999871 oz t

Pennyweight to Troy Ounce conversion table

Standard reference values for converting pennyweights to troy ounces:

Pennyweight [dwt]Troy Ounce [oz t]
0.010.0005
0.10.0049999999
10.0499999987
20.0999999974
30.1499999961
40.1999999949
50.2499999936
100.4999999871
200.9999999743
301.4999999614
401.9999999486
502.4999999357
1004.9999998714
50024.999999357
100049.999998714

Frequently asked questions

How many troy ounces is 1 pennyweight?
1 pennyweight equals 0.0499999987 troy ounce.
How do I convert pennyweights to troy ounces?
Multiply the value in pennyweights by 0.0499999987 to get troy ounces.
How do I convert troy ounces back to pennyweights?
Multiply the value in troy ounces by 20.0000005144, or use the Troy Ounce to Pennyweight converter.
How many troy ounces is 100 pennyweights?
100 pennyweights equals 4.9999998714 troy ounces, because 100 × 0.0499999987 = 4.9999998714.

Convert Pennyweight to other weight units

Show all Pennyweight 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 dwt = 0.0499999987 oz t) verified against the following authoritative sources:

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