The first mechanical calculator was invented in.
The first mechanical calculator was invented in 1647.
A mechanical calculator, or calculating machine, is a mechanical device used to perform automatically the basic operations of arithmetic. Most mechanical calculators were comparable in size to small desktop computers and have been rendered obsolete by the advent of the electronic calculator.
Two decades after Schickard's supposedly failed attempt, in 1642, Blaise Pascal decisively solved these particular problems with his invention of the mechanical calculator. Co-opted into his father's labour as tax collector in Rouen, Pascal designed the calculator to help in the large amount of tedious arithmetic required; it was called Pascal's Calculator or Pascaline.