Convert Square Foot (ft²) to Barn (b (area)) instantly.
About these units
Square Foot (ft²)
A square foot is the area of a square one foot on each side. It is widely used in the United States, the UK (historically), Canada (in real estate), and other regions where imperial units remain culturally influential. Square feet dominate property listings, architectural blueprints, and interior design specifications in the US. The measurement provides an intuitive scale for rooms and buildings, fitting well with common human-scaled dimensions. Although metrication has reduced its use worldwide, the square foot remains deeply embedded in construction codes, real estate markets, and consumer expectations in countries that continue to rely on imperial or hybrid systems. Its survival highlights the cultural persistence of traditional measurement systems despite global standardization.
Barn (b (area))
The barn is an area unit used almost exclusively in nuclear and particle physics, equal to 10⁻²⁸ square meters. Despite its incredibly tiny size, the barn emerged from humorous origins: early nuclear physicists joked that certain atomic nuclei were "as big as a barn" compared to the particles trying to hit them. The barn quantifies interaction cross-sections—essentially probabilities of particles colliding or interacting with nuclei. Because fundamental forces operate at extremely small scales, typical cross-section values lie in the microbarn, nanobarn, or picobarn range. The barn is essential for describing reaction rates in particle accelerators, nuclear reactors, and astrophysical processes such as stellar fusion.