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":
    :   └─Margaret Sieren (1 Aug 1881 Keokuk County, Iowa - 30 Nov 1980 Keota, Keokuk County, Iowa)
    :    John Jacob Merz (3 Jan 1875 Keokuk County, Iowa - 27 Feb 1933 Harper, Keokuk County Iowa)
    :    (m. 23 Oct 1902 Ss. Peter & Paul Catholic Church, Clear Creek Township, Keokuk, County, Iowa)
    :       ├─Peter Richard Merz (30 Jul 1903 Near Harper, Keokuk County, Iowa -     :       │ 11 Feb 1980 Harper, Keokuk County Iowa) =>
    :       │ + Margaret Theresa Sondag (5 Nov 1903 Harper, Keokuk County, Iowa - 20 Feb 1988 Sigourney Care Center,     :       │ Sigourney, Keokuk County, Iowa)(m. 8 Feb 1927 St. Elizabeth Church, Harper, Keokuk     :       │ County, Iowa)
    :       ├─Mary J Merz (ca 1917 - ??) =>
    :       │ + Leander M Berg
    :       ├─John A Merz (17 Jan 1922 - 1 Apr 1970)
    :       │ + Martha J Page (8 Mar 1938 Washington, Washington County, Iowa - 29 Jul 2020 Mercy Hospital, Iowa     :       │ City, Johnson County, Iowa)(m. 8 Nov 1958 Keota, Keokuk County, Iowa)