Convert Stone (st) to Poundal (pdl) instantly.
About these units
Stone (st)
The stone equals 14 pounds, or approximately 6.35029 kilograms, and is commonly used in the United Kingdom and Ireland for expressing human body weight. It has deep traditional roots, originating from stones used as counterweights in early commerce. Although largely replaced by metric units in most applications, the stone remains emotionally and culturally significant for personal weight expression in the UK. Many people find it more intuitive and relatable than kilograms due to long-standing social habits. The stone's endurance highlights how measurement systems reflect cultural identity as much as mathematical convenience. It is one of the few units still commonly used in conversation but not in scientific or industrial contexts.
Poundal (pdl)
The poundal is the unit of force in the foot–pound–second (FPS) system, defined as the force that accelerates a one-pound mass at one foot per second squared. Although a force unit, it interacts with mass units in engineering contexts similarly to inertial mass units. Historically, poundals appeared in older physics textbooks and engineering references before the widespread adoption of SI units. Their use has declined dramatically, but they remain part of the history of classical mechanics education. The poundal exemplifies how many different systems attempted to rationalize force, mass, and acceleration before the international community converged on the SI newton.