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":
    Peter Paul Buch (15 Sep 1793 Tunsdorf, Saarland, Germany -     13 Sep 1875 Clear Creek Township, Keokuk County, Iowa)
       └─Constantine Dionysius Buch, Sr (10 May 1832 Tunsdorf, Saarland, Germany -         5 Apr 1908 At Home on Farm, Clear Creek Township, Keokuk County, Iowa)
        Magdalena Streit (16 Nov 1838 Wehingen, Merzig-Wadern, Saarland, Germany - 18 Oct 1900 Clear Creek         Township, Keokuk County, Iowa)(m. 6 May 1858 Ss. Peter & Paul Catholic Church, Clear Creek Township,         Keokuk, County, Iowa)
           ├─Anna Rosalia Buch (2 May 1859 Talleyrand, Keokuk County, Iowa -            │ 27 Aug 1929 bur.Clear Creek Township, Keokuk County, Iowa) =>
           │ + Peter Hammes, Sr. (26 May 1852 Feyen, Near Trier, Merzig-Wadern, Germany -            │ 20 Apr 1929 Keokuk County, Iowa)(m. 19 Apr 1877)
           ├─Mathias Buch (21 Dec 1860 - 30 May 1864 bur.Clear Creek Township, Keokuk County, Iowa)
           ├─Catharine Buch (9 Feb 1863 - 9 Aug 1863 bur.Clear Creek Township, Keokuk County, Iowa)
           ├─Constantine Dionysius Buch, Jr (21 Aug 1864 -            │ 29 Dec 1954 bur.Clear Creek Township, Keokuk County, Iowa)
           │ + Anna Peiffer (13 Apr 1868 - 12 May 1958 bur.Clear Creek Township, Keokuk County, Iowa)
           ├─Mary Buch (9 Jun 1866 - 1 Mar 1939)