Mass and Weight · Unit Converter

Convert Pennyweight to Femtogram

Convert pennyweights to femtograms instantly. 1 pennyweight = 1.555174e+15 femtogram — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Femtogram 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

Femtogram

What is a femtogram?

A femtogram (fg) equals 10^-18 kilogram.

Origin of the femtogram

From the SI prefix 'femto-' (from Danish/Norwegian 'femten', fifteen).

Where it is used

Nanotechnology and high-sensitivity mass spectrometry.

When and where it was developed

The femto- prefix was adopted by the CGPM in 1975.

Pennyweight to Femtogram conversion formula

The relationship between pennyweights and femtograms:

1 dwt = 1.555174e+15 fg
1 fg = 6.430149e-16 dwt

To convert pennyweights to femtograms, multiply the value in pennyweights by 1.555174e+15. To reverse, multiply femtograms by 6.430149e-16.

How to use this converter

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

Step-by-step: convert pennyweights to femtograms

  1. Write down the value in pennyweights (dwt).
  2. Multiply that value by the factor 1.555174e+15.
  3. The product is the equivalent value in femtograms (fg).
  4. To reverse, multiply the femtogram value by 6.430149e-16.

Worked examples

Example 1 — Convert 1 dwt to fg:
1 × 1.555174e+15 = 1.555174e+15 fg

Example 2 — Convert 100 dwt to fg:
100 × 1.555174e+15 = 1.555174e+17 fg

Real-world example — Centimeter to wavelength scale

One pennyweight equals 10 million femtograms. Physics curricula use this kind of conversion to relate everyday measurements to atomic and optical scales.

1 dwt × 1.555174e+15 = 1.555174e+15 fg

Real-world example — Small-scale to atomic-scale

One pennyweight equals 10 million femtograms — useful for physics curricula that relate everyday measurements to atomic and optical scales.

1 dwt × 1.555174e+15 = 1.555174e+15 fg

Pennyweight to Femtogram conversion table

Standard reference values for converting pennyweights to femtograms:

Pennyweight [dwt]Femtogram [fg]
0.011.555174e+13
0.11.555174e+14
11.555174e+15
23.110348e+15
34.665521e+15
46.220695e+15
57.775869e+15
101.555174e+16
203.110348e+16
304.665521e+16
406.220695e+16
507.775869e+16
1001.555174e+17
5007.775869e+17
10001.555174e+18

Frequently asked questions

How many femtograms is 1 pennyweight?
1 pennyweight equals 1.555174e+15 femtogram.
How do I convert pennyweights to femtograms?
Multiply the value in pennyweights by 1.555174e+15 to get femtograms.
How do I convert femtograms back to pennyweights?
Multiply the value in femtograms by 6.430149e-16, or use the Femtogram to Pennyweight converter.
How many femtograms is 100 pennyweights?
100 pennyweights equals 1.555174e+17 femtograms, because 100 × 1.555174e+15 = 1.555174e+17.

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+15 fg) verified against the following authoritative sources:

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