A reasoner is a piece of software able to infer logical consequences from a set of asserted facts or axioms.
Reasoner may also refer to: 20474 Reasoner, a main-belt asteroid New Reasoner, a political magazine Reasoners Run, a stream in Ohio, U.S. Solver, software that solves a family of mathematical problems by inferring consequences from logical rules USS Reasoner (FF-1063), a Knox class frigate
People with the surname Elsie Reasoner Ralph (1878–1913), first American female war correspondent Frank S. Reasoner (1937–1965), United States Marine Corps officer Harry Reasoner (1923–1991), American journalist James Reasoner (born 1953), American novelist Marty Reasoner (born 1977), American ice hockey player Mike Reasoner (born 1960), American politician Stephen M. Reasoner (1944–2004), American judge Tommy Reasoner (born 1967), American soccer player