Many Web sites have problems with type size; either headings are too large, or - more seriously - body text is too small to comfortably read.
Heading size
The default size for headings on the Web is too large. Headings do not need to be giant. For example, one and a half times the body text size is usually plenty.
Remember that you have other options which allow you to emphasise headings without increasing their size. For example, you could make heading text bold, or you could include a horizontal rule underneath the heading. These techniques can be especially helpful when you need multiple levels of heading.
Body text size
Body text on the Web is often too small to read comfortably. Although most browsers have a feature to increase text size, this does not always work correctly, and users should not need to do this to read your page easily (unless, perhaps, they have poor vision).
Bear in mind these general guidelines:
- If text does not need to be small, why not pick a comfortable, medium size?
- As a minimum, specify text one size larger than the smallest you find comfortable.
Technical problems
Older versions of Macintosh browsers display text significantly smaller than Windows browsers.
Even on Windows, some browsers may occasionally display text a little smaller than specified.
You can reduce these problems by defining text size in pixels using a stylesheet, but this has its own disadvantage: due to a limitation in Internet Explorer and old versions of Netscape, text specified in pixels cannot be resized by the user in those browsers.
These factors make it important that you err on the large side with text size specifications.
DALnet
This site is about the DALnet Internet Relay Chat network (a system for 'chatting', by typing, with other Internet users).
The default text size is tiny so that it can be rather difficult to read. The small text size also makes the text columns too wide for comfort. Avoid making this kind of mistake with your own pages.
Consistency
You should be consistent with text sizes. Try to restrict yourself to two or three different sizes on each page. This helps give a more professional appearance.
Text not intended to be read
If there is text on your page which nobody will want to read - for example, copyright notices or legal disclaimers - feel free to make it as small as you like. The text does not need to be read, so it may as well be as small as possible in order to reduce its impact.
You might even want to use a dull or faded colour for that text, so that it is less obvious against the background. (That is the approach taken for copyright messages on this site.)