Find rounding calculators at HelpingWithMath.com, CalculatorSoup.com, MathWarehouse.com and TheCalculator.com. HelpingWithMath.com also offers instructions for rounding numbers manually, along with worksheets and matching cards to help students practice.
In addition to a rounding calculator, TheCalculator.com offers more than 750 calculation tools, including a mortgage calculator and calorie counter.
Rounding a number means replacing it with another number that is nearly equal but is shorter or simpler. People round numbers for many reasons, including obtaining a number that is easier to report or communicate than the original precise value. The concept of rounding is very old, as evidenced by the ancient clay tablets with tables of rounded numbers that archaeologists found in Mesopotamia.