<!doctype html> <html> <body style='margin:0px'> <img id='sizer'/> <script> // The desired size should be specified in the url in the search portion // like this ?widthDimension:heightDimension. var unitMatch = '([0-9]+[a-zA-Z]+)'; var searchParser = new RegExp('\\?' + unitMatch + '(?:\\:' + unitMatch + ')'); var parsedParameters = searchParser.exec(window.location.search); // Set the sizes. var elementToSize = document.getElementById('sizer'); var width = parsedParameters[1]; elementToSize.style.width = width; var height = parsedParameters[2]; elementToSize.style.height = height; </script> </body> </html>