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":
Capt Robert McClenachan, Jr
(19 Apr 1747 Augusta County, Virginia, USA - 10 Oct 1774 Point Pleasant, Mason County, West Virginia, USA)
Catherine Madison
(1754 Augusta County, Virginia, USA - 18 Jul 1818 Buffalo, Putnam County, West Virginia, USA)
         ├─Robert McClanachan, III
(1771 Augusta County, Virginia, USA - 1824 Barren County, Kentucky, USA)
         │ + Sarah (Sally) Abney
(1769 Augusta County, Virginia, USA - 11 Sep 1853 Barren County, Kentucky, USA)
         └─John Burns McClanahan, Sr
(Dec 1774 Augusta County, Virginia, USA - Apr 1847 Lawrenceton, Ste Genevieve County, Missouri, USA)
          Lydia Burns
(1774 Washington County, Pennsylvania, USA - 1 May 1860 McBride, Perry County, Missouri, USA)
                   ├─Michael Burns McClanahan
(24 Jul 1816 Ste Genevieve, Ste Genevieve County, Missouri, USA -                    │ 12 Dec 1868 Kingston, Madison County, Arkansas, USA)
                   ├─Spicer C McClanahan
(1824 Ste Genevieve, Ste Genevieve County, Missouri, USA - 1881 Sulphur Springs, Hopkins County, Texas, USA)
                   ├─William Madison McClanahan
(25 Aug 1812 Lawrenceton, Ste Genevieve County, Missouri, USA -                    │ 13 Oct 1869 Bloomsdale, Ste Genevieve County, Missouri, USA)
                   ├─James McClanahan
(14 Mar 1798 Ste Genevieve, Ste Genevieve County, Missouri, USA - 1873 Yoakum, Lavaca County, Texas, USA)
                   ├─Mary Ann McLanahan
(18 Jan 1808 Ste Genevieve, Ste Genevieve County, Missouri, USA - 1855 Ste Genevieve County, Missouri, USA)
                   ├─John Burns McClanahan, Jr
(1814 Ste Genevieve, Ste Genevieve County, Missouri, USA - 1908)
                   │ + Living
                   ├─Catherine McClanahan
(1797 Ste Genevieve County, Missouri, USA - 1837)
                   └─Robert McClanahan
(1820 Ste Genevieve County, Missouri, USA - ??)