Free Online Calculators

Our free online calculators suite are for everyday use includes BMI, moon phases, carbon footprint, biorhythms alcohol and fuel calculators. In 1642, Blaise Pascal, a French intellectual and mathematics prodigy, designed the first mechanical calculator. His invention used geared wheels and could directly add, subtract, multiply, and divide. Later, Gottfried Leibniz refined the concept, but it wasn’t until 1820 that Thomas de Colmar patented the Arithmometer, a fully operational four-function mechanical calculator. By the 20th century there was a seismic shift with the advent of electronic calculators. Descendants of Blaise Pascal’s digital arithmetic machine, these devices became smaller, faster, and less laborious to use. By the 1990s, pocket calculators had become commonplace, rendering the slide rule obsolete.