The easiest and most effective way to change the font size – to change the scale of pages. Hold down the Ctrl key and roll the mouse wheel down to decrease font size, up to boost. You can also press Ctrl and press " + " that will lead to the same result. This method is suitable for any browser, but requires a change not only font size but the entire page zoom. Normal page view is zoom 100%, zoom in, automatically increases the font. If you want to change the font size without changing other parameters, you need to go to your browser settings.
If you need to change the font size in Mozilla Firefox (meaning the latest version), click the Firefox button in the upper left corner, select "Settings" and click the top item in the list, which is also called "Settings". Open the third tab is "Contents". Under "Fonts & colors" select the font and size (from 9-th to 72-th). Click "Advanced" on the right side and uncheck "Allow websites to choose their own fonts".
In popular Opera browser to change the font size by selecting in the menu "Settings" - "General settings". On the tab "Web page" click on the font name in the dialog box, select the size. In this window you can change the page size, making the font smaller or larger. In Opera you can also adjust the size of the so-called monospace font that has the characters the same width.
In Internet Explorer click "Page" at the top of the window, locate "font Size" and set any: the largest, large, medium, small and smallest.
If you need to change the font size in Google Chrome, click on settings in the upper right corner, select "Settings", "Advanced" and find "font Size".