Mass and Weight · Unit Converter

Convert Pennyweight to Gigagram

Convert pennyweights to gigagrams instantly. 1 pennyweight = 1.555174e-9 gigagram — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Gigagram 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.

Metric / SI

Gigagram

What is a gigagram?

A gigagram (Gg) equals 10^6 kilograms, the same as 1,000 metric tons.

Origin of the gigagram

From the SI prefix 'giga-' (from Greek 'gigas', giant).

Where it is used

Bulk commodity, emissions, and freight accounting.

When and where it was developed

The giga- prefix entered the SI in 1960.

Pennyweight to Gigagram conversion formula

The relationship between pennyweights and gigagrams:

1 dwt = 1.555174e-9 Gg
1 Gg = 6.430149e+8 dwt

To convert pennyweights to gigagrams, multiply the value in pennyweights by 1.555174e-9. To reverse, multiply gigagrams by 6.430149e+8.

How to use this converter

Type a value into the calculator. The result in gigagrams updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Gigagram to Pennyweight converter for the reverse direction.

Step-by-step: convert pennyweights to gigagrams

  1. Write down the value in pennyweights (dwt).
  2. Multiply that value by the factor 1.555174e-9.
  3. The product is the equivalent value in gigagrams (Gg).
  4. To reverse, multiply the gigagram value by 6.430149e+8.

Worked examples

Example 1 — Convert 1 dwt to Gg:
1 × 1.555174e-9 = 1.555174e-9 Gg

Example 2 — Convert 100 dwt to Gg:
100 × 1.555174e-9 = 1.555174e-7 Gg

Real-world example — Postcard and small-object dimensions

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

5 dwt × 1.555174e-9 = 7.775869e-9 Gg

Real-world example — Ruler-scale measurements

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

30 dwt × 1.555174e-9 = 4.665521e-8 Gg

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 gigagrams daily when mixing metric and imperial tools.

10 dwt × 1.555174e-9 = 1.555174e-8 Gg

Pennyweight to Gigagram conversion table

Standard reference values for converting pennyweights to gigagrams:

Pennyweight [dwt]Gigagram [Gg]
0.011.555174e-11
0.11.555174e-10
11.555174e-9
23.110348e-9
34.665521e-9
46.220695e-9
57.775869e-9
101.555174e-8
203.110348e-8
304.665521e-8
406.220695e-8
507.775869e-8
1001.555174e-7
5007.775869e-7
10001.555174e-6

Frequently asked questions

How many gigagrams is 1 pennyweight?
1 pennyweight equals 1.555174e-9 gigagram.
How do I convert pennyweights to gigagrams?
Multiply the value in pennyweights by 1.555174e-9 to get gigagrams.
How do I convert gigagrams back to pennyweights?
Multiply the value in gigagrams by 6.430149e+8, or use the Gigagram to Pennyweight converter.
How many gigagrams is 100 pennyweights?
100 pennyweights equals 1.555174e-7 gigagrams, because 100 × 1.555174e-9 = 1.555174e-7.

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 = 1.555174e-9 Gg) verified against the following authoritative sources:

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