The paper length is not relevant since the chart flows from one page to the next.
Mobile
in.
mm
Staand
2.75
70
For smart phones, not for printing
Liggend
5.5
140
For smart phones, not for printing
International
in.
mm
A5 Staand
5.82
148
A4 Staand
8.25
210
Also A5 Liggend
A4 Liggend
11.71
297
Also A3 Liggend
A3 Liggend
16.54
420
USA & Canada
in.
mm
Letter Staand
8.5
216
Also Legal Staand
Letter Liggend
11
279
Legal Liggend
14
356
Also Ledger Staand
Ledger Liggend
17
432
The Text+ programs assume that the right and left margins are each about 25mm (1/2 inch) wide.
On the Format for Printing page, differences in page margins can be accommodated by the "fudge factor":
Van den Heuvel Genealogiepagina
ca. 1735 - 1787 (~ 52 Jaar)
Dammis Theunisz Kruijk 
(ged.12 dec 1756 Oostvoorne - begr.18 nov 1809 Rockanje)(huw. 6 feb 1785 Rockanje)