Free online calculators are similar to the physical calculators that people use at home and at the office. The only difference is that everything is displayed on the computer monitor or tablet screen. You do not need to carry a calculator with you anymore as online calculators are perfect substitutes.
These days, there is no need to spend money on a calculator, as most calculations can be done online. People can even download and install these calculators on a PC or on a mobile device. Most PC operating systems come with a preinstalled calculator. Apart from simple calculations, people can even use the scientific calculator online when working with trigonometry and logarithms.