The paper length is not relevant since the chart flows from one page to the next.
Mobile
in.
mm
Portrait
2.75
70
For smart phones, not for printing
Landscape
5.5
140
For smart phones, not for printing
USA & Canada
in.
mm
Letter Portrait
8.5
216
Also Legal Portrait
Letter Landscape
11
279
Legal Landscape
14
356
Also Ledger Portrait
Ledger Landscape
17
432
International
in.
mm
A5 Portrait
5.82
148
A4 Portrait
8.25
210
Also A5 Landscape
A4 Landscape
11.71
297
Also A3 Landscape
A3 Landscape
16.54
420
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":
Arthur William TORR
(9 Jul 1884 Wariora, New Zealand - 20 Dec 1962 Bunbury, Western Australia, Australia)
Jean RYALL
(7 Jun 1889 Horsham, Victoria, Australia - 13 Feb 1970 Perth, Western Australia, Australia)
└─Ena Joyce TORR
(22 Jun 1915 Donnybrook, Western Australia, Australia - 2 Mar 2011 Mandurah, Western Australia, Australia)
Leonard Joseph WATSON
(12 Apr 1909 - 20 Jul 1972 Bunbury, Western Australia, Australia)
1884 - 1962 (78 years)
Jean RYALL 
(7 Jun 1889 Horsham, Victoria, Australia - 13 Feb 1970 Perth, Western Australia, Australia)