Trapezium (trapezoid) calculator will help you calculate the long diagonal of the trapezium, the short diagonal of the trapezium, the side length, height, area and perimeter of the trapezium.

Using this calculator you can calculate the percentage concentration, also called the percentage by weight of chemical substances in mixtures and solutions.

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.