Page size and margins can be customized for export. To open the "Page size and Margins" dialog click the edit button on the right in the "Page and Margins" section on the Export Profile editor dialog.

Page size

There are several predefined page sizes, which you can select from. Once you selected the page size, you can also choose between landscape and portrait orientation:

You can also define a custom page size by selecting "Custom" value from the page size drop-down. In this case you can enter any custom value for the width and height:

Margins

Margin can also be customized on the "Page size and Margins" dialog. Just select the unit on the top part and on the bottom part of it, just enter the desired values for each margins. The given values with the selected unit will be used during the export: