Blank Stair is a free tool for calculating the number of steps required to construct a set of stairs. The app allows you to calculate the number of steps in an open-air staircase, which is very convenient for builders and carpenters.

The app is built into two sections: a staircase calculator and a balluster spacing calculator.

In the first section, you need to enter the overall height of the staircase and you will get the number of running strings. The number of steps is the sum of the numbers of running strings. In the second section, you need to enter the width and height of the opening.

If you cut steps the old-fashioned way, you just need to use the rise and run cut values from this page to mark your stringers. However, a far superior method of marking stringers is to use the running stringer layout. Here is a quick guide:

Using this method will eliminate marking errors. Nearly perfect stairs every time.