Editing Paper size (section)

===Traditional inch-based paper sizes<span class="anchor" id="Foolscap"></span>===
[[File:Paper size - US system.svg|thumb|upright=1.5|Traditional and standardized paper formats still relevant in the US]]

Traditionally, a number of different sizes were defined for large sheets of paper, and paper sizes were defined by the sheet name and the number of times it had been folded. Thus a full sheet of "royal" paper was 25 × 20 inches, and "royal octavo" was this size folded three times, so as to make eight sheets, and was thus 10 × {{frac|6|1|4}} inches. Royal sizes were used for posters and billboards.

{| class="wikitable"
|+ Common divisions and their abbreviations
|-
! Name
! Abbr. !! Folds !! Leaves !! Pages
|-
! [[Folio (printing)|Folio]]<!-- , Folacio -->
| fo, f || 1 || 2 || 4
|-
! Quarto
|  4to || 2 || 4 || 8
|-
! Sexto, sixmo
|  6to, 6mo || 3 || 6 || 12
|-
! Octavo<!-- , Belagionastic -->
|  8vo || 3 || 8 || 16
|-
! Duodecimo, twelvemo
| 12mo || 4 || 12 || 24
|-
! Sextodecimo, sixteenmo
| 16mo || 4 || 16 || 32
|}

{{cleanup|table|reason=Badly sourced collection of sizes, correct values may vary, variation through trimming is ignored and some designations are confusing, in short: it is probably full of mistakes.|date=January 2020}}
Imperial sizes were used in the United Kingdom and its territories and some survived in US book printing.

{| class="wikitable"
|+ Imperial paper sizes
|-
! Name !! Variant
! inch × inch !! mm × mm !!title="aspect ratio"| AR
|-
! Emperor
| UK || {{size|48|72|in|mm}} || 1.5
|-
! Quad Royal
| US || {{size|40|50|in|mm}} || 1.25
|-
! Quad Demy
| US || {{size|35|45|in|mm}} || 1.2857
|-
! Antiquarian
| UK || {{size|31|53|in|mm}} || 1.7097
|-
! Grand Eagle
| UK || {{size|28+3/4|42|in|mm}} || 1.4609
|-
! Double Elephant
| UK || {{size|26+3/4|40|in|mm}} || 1.4984
|-
! Atlas
| UK || {{size|26|34|in|mm}} || 1.3077
|-
! Double Royal
| US || {{size|25|40|in|mm}}  || 1.6
|-
! Colombier
| UK || {{size|23+1/2|34+1/2|in|mm}} || 1.4681
|-
!rowspan=2| Double Demy
| UK || {{size|22+1/2|35+1/2|in|mm}} || 1.5{{overline|7}}
|-
| US || {{size|22+1/2|35|in|mm}} || 1.{{overline|5}}
|-
! Imperial
| UK || {{size|22|30|in|mm}} || 1.3636 <!-- 9 × 7 -->
|-
! Double Large Post
| UK || {{size|21|33|in|mm}} || 1.5713
|-
! {{visible anchor|Elephant}}
| both || {{size|23|28|in|mm}} || 1.2174
|-
! Princess
| UK || {{size|22+1/2|28|in|mm}} || 1.3023
|-
! Cartridge
| UK || {{size|21|26|in|mm}} || 1.2381
|-
! Royal
| both || {{size|20|25|in|mm}} || 1.25
|-
! Sheet, Half Post<!--this seems incorrect!-->
| UK || {{size|19+1/2|23+1/2|in|mm}} || 1.2051
|-
! Double Post
| UK || {{size|19|30+1/2|in|mm}} || 1.6052
|-
! Super Royal
| UK || {{size|19|27|in|mm}} || 1.4203
|-
! Broadsheet
| US || {{size|18|24|in|mm}} || 1.{{overline|3}}
|-
!rowspan=2| Medium
| UK || {{size|17+1/2|23|in|mm}} || 1.2425
|-
| US || {{size|18|23|in|mm}} || 1.2{{overline|7}}
|-
! Demy<span class="anchor" id="Demy"></span><!--Please leave. Text in another article links here.-->
| both || {{size|17+1/2|22+1/2|in|mm}} || 1.2857
|-
! Copy Draught
| UK || {{size|16|20|in|mm}} || 1.25
|-
!rowspan=2| Large Post
| UK || {{size|15+1/2|20|in|mm}} || 1.2903
|-
| US || {{size|16+1/2|21|in|mm}} || 1.{{overline|27}}
|-
!rowspan=2|Post
| UK || {{size|15+1/2|19+1/4|in|mm}} || 1.2419
|-
| US || {{size|15+1/2|19+1/2|in|mm}} || 1.2581
|-
! Crown
| both || {{size|15|20|in|mm}} || 1.{{overline|3}}
|-
! Pinched Post
| UK || {{size|14+3/4|18+1/2|in|mm}} || 1.2533
|-
!rowspan=2| Foolscap
| UK || {{size|13|16|in|mm}} || 1.2303
|-
| US || {{size|13+1/2|17|in|mm}} || 1.2595
|-
!rowspan=2| [[Foolscap Folio]]
| UK || {{size|13|8|in|mm}} || 1.6256
|-
| US || {{size|13+1/2|8+1/2|in|mm}} || 1.5880
|-
! Small Foolscap
| UK || {{size|13+1/4|16+1/2|in|mm}} || 1.2453
|-
! Brief
| UK || {{size|13+1/2|16|in|mm}} || 1.1852
|-
! Pott
| UK || {{size|12+1/2|15|in|mm}} || 1.2
|-
! Quarto
| <!-- 8 × 10 --> US || {{size|9|11|in|mm}} || 1.{{overline|2}}
|-
! Executive, Monarch
| US || {{size|7+1/4|10+1/2|in|mm}} || 1.4483
|}