Significant figures are important because they show how precise a number is. Precision means how close a value is to the real or true value. In science and measurements, it is not enough to just write numbers. You must also show how accurate those numbers are. A Sig Fig Calculator helps maintain this accuracy. When you add or multiply numbers, the calculator ensures the final result does not show more precision than allowed. This is very important in chemistry experiments, physics problems, engineering designs, and lab reports.