Easily and quickly calculate the sum of the geometric sequence, you will determine the value of the nth term.

With this calculator, we will find out what ventilation efficiency should have depending on the size, height and type of room, e.g. in the kitchen, bathroom or toilet. The ventilation calculator will help us choose the right fan for the selected room, e.g. it will facilitate the selection of the hood for the kitchen.

The Body Fat percentage calculator will help you calculate the amount of fat stored in your body. It uses a method of measuring skin folds in three different places on the body.