Current releases of the Mozilla Firefox webpage Browsers offers Page Size and Page View functions as follows:
Firefox tools menu
Select the Tools drop-down menu, and Web Developer sub-menu; and click Responsive Design View
Responsive Deisgn View
Select the size - if not custom, from 320 wide x 480 high to 1920 wide x 900 high. The Rotate button swaps width and height of size.

Internet Explorer 6 webpage Browsers and Internet Explorer 9 pinned site windows offer a Page Printer function as follows:
Internet Explorer File Menu Pinned Window Tools Print Menu
Select the File drop-down menu or Print sub-menu, and click Page Setup
Page setup
Select the size - if not custom, from letter to A4. The sizes vary and are based on Printer selection.

Google Chrome webpage Browsers and others can offer Page Zoom function as follows:
Chrome Zoom
Select the - or + to Zoom the page out and in from the intial 100%.


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