HTTP Get requests do not include the size of the screen nor the size of the browser. There is nothing that any serverside technology can ever do to change that. You could emit some script that performs an immediate postback whenever you don't know the sizes. This way you could be assured of knowing this information, in the case that the browser supports script at all. If the browser doesn't support script, you will never know its size information. Most people who want this information, are using it to "reflow" their grid/absolute positioning based form designs. I would suggest you stop using grid based designs, and switch to flow based layout, as HTML is intended to be used.