Convert Femtogram (fg) to Pennyweight (pwt) instantly.
About these units
Femtogram (fg)
A femtogram is 10⁻¹⁵ grams, an extraordinarily small unit used primarily in molecular biology, analytical chemistry, and particle science. At this scale, masses correspond to small clusters of molecules, fragments of genetic material, or trace contaminants in environmental samples. In genomics, for example, the femtogram level may represent the mass of DNA extracted from just a few cells, pushing the limits of current sequencing technologies. Advanced mass spectrometers and nanoscale resonators can detect femtogram-level differences, revealing chemical changes invisible at larger scales. The femtogram symbolizes the reach of modern science into realms once thought beyond measurement. As techniques continue to improve, femtogram-level precision will become increasingly common in nanotechnology and biophysics.
Pennyweight (pwt)
The pennyweight, equal to 1/20 of a troy ounce or 1.55517384 grams, is a unit used primarily in the precious metals and jewelry industries. Its origins lie in medieval English coinage, when the weight of silver pennies provided a practical standard for small masses. Jewelers continue to use the pennyweight because many traditional pricing structures and metalworking conventions are built around troy-based subdivisions. For gold, silver, and dental alloys, the pennyweight remains easier to work with than grams due to long-established norms. Even though the metric system is now dominant scientifically, the pennyweight persists because industries tied to history—especially those involving money and precious goods—tend to maintain deeply rooted practices.