For more on [http://context.aanhet.net/svn/contextman/context-reference/en/co-pagedesign.pdf layout and page design] see the [http://context.aanhet.net/svn/contextman/context-reference/en/co-pagedesign.pdf manual chapter].
Page size and paper size are set with {{cmd|setuppapersize}}. Many paper sizes are already defined by name; see the list of [[PaperSizes|paper sizes]]. To define a new paper size, use {{cmd|definepapersize}}.