Calculation of open area
The formulae on this page are used to calculate the open area of a user defined perforation. The results are calculated automatically by clicking the "Submit" button when you have entered all the relevant figures.
Calculation of open area: round holes, triangular pitch

Calculation of open area: round holes, rectangular pitch

Calculation of open area: square holes, rectangular pitch

Calculation of open area: square holes, staggered pitch

Calculation of open area: slot holes, staggered pitch

Calculation of open area: rectangular holes, staggered pitch

Tip
Changing the size of the holes or the pitch will result in a larger or smaller percentage of open area.
Please note
The formulae do not indicate whether the suggested perforation is possible, they are to be used solely for calculation of the open area. The pitch dimension must in general be greater than minimum the hole size dimension + thickness of the material.
Reservations
Please note that these are a guide only. We cannot be held responsible for any mistakes in the results of the calculations made on this page, for example errors made when entering values or errors in the formulae themselves.