Nevermind, the answer is simple:

\setuplayout[

backspace=0mm,
topspace=0mm,
margin=0mm,
header=0mm,
footer=0mm
                width=600px,
                height=440px
]



On Fri, Mar 4, 2011 at 4:29 PM, John Haltiwanger <john.haltiwanger@gmail.com
> wrote:

> Hi all,
>
> I would have though the following code would produce text flush to the
> edges of the "paper", but there is significant whitespace on the right and
> bottom sides. Probably there is an obvious setting, but it eludes me now:
>
> \definepapersize[short][width=600px,height=440px]
> \setuppapersize[short][short]
>
> \setuplayout[
> backspace=0mm,
>  topspace=0mm,
> margin=0mm,
> header=0mm,
>  footer=0mm
> ]
>
> \setupindenting[none]
>
> \setupwhitespace[medium]
> \setupinterlinespace[22pt]
>
> \starttext
>
> \input Tufte
>
> \input Knuth
>
> \input Tufte
>
> \stoptext
>