Choose your own font size.

In most cases you can adjust the font size or zoom factor by simply turning your mouse wheel while keeping pressed the "Ctrl" key.

Alternatively, you can try the following, depending on your browser:

Internet Explorer and Mozilla Firefox

Adjust font size in the browser menu "View" (bigger, medium, smaller, …).

Opera

Change the zoom factor in the browser menu "View". Or change your font size with +, resp. - using your keyboard.

Safari

Change font size in the browser menu "View".

Google Chrome

Open the "Menu" by clicking on the wrench icon in the top right corner and adjust the zoom factor.