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":
         └─Daniel Mathena
(1638 Canterbury, Kent, England - 14 Oct 1685 Hope Plantation, Stafford County, Virginia, USA)
          Sarah Wentworth
(1648 Canterbury, Kent, England - 1700 Stafford County, Virginia, USA)
                   ├─William Wentworth Mathena
(1666 Charles County, Maryland, USA - Dec 1705 Hope Plantation, Stafford County, Virginia, USA)
                   │ Frances ?? (w of Wm Mason, Wm Matheny)
(1666 Stafford County, Virginia, USA - ??)
                   │          └─Daniel Matheny
(Hope Plantation, Stafford County, Virginia, USA;1693 - 20 Jan 1750) =>
                   │           + Mary Routt
(26 Feb 1687/88 Northumberland County, Virginia, USA - 12 Jan 1750 Stafford County, Virginia, USA)
                   ├─Elizabeth Matheny
(1671 Charles County, Maryland, USA - 1674 Stafford County, Virginia, USA)
                   ├─Sarah Matheny
(1668 Maryland, USA - Abt 1679 Charles County, Maryland, USA)
                   ├─Suzanna Matheny
(Abt 1664 Charles County, Maryland, USA - Abt 1708 Overwharton Parish, Stafford County, Virginia, USA)
                   └─Mary Matheny
(1669 Charles County, Maryland, USA - ??)