The correct way
Do not increase the text size for these people. Let people with large screens zoom in manually. Use em's instead of px, em is a unit relative to the parent or body font size. This article, CSS Font-Size: em vs. px vs. pt vs. percent, has a good reference about units and it usage. Setting ems allows most modern browsers to scale the font size appropriately as the end user zooms in with ctrl + +
The transform method
This method is only compatible with recent browsers
(see the reference on can I use about scale )
-webkit-transform-origin: 0 0;
-moz-transform-origin: 0 0;
-ms-transform-origin: 0 0;
-o-transform-origin: 0 0;
transform-origin: 0 0;
I posted a code on jsfiddle that you can check here, I use
scale(2) which equals to 200%.
The non standard method
try the zoom property on your body in CSS. This method is not a standard and support may be dropped, however, for now it is supported by most modern browsers.
To test support in your browser of choice, follow this link, also on fiddle: and measure the size of the image
Check this reference about zoom.