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Re: Font size


From: Leo Smith
Date: Jun 3, 2002 11:04AM

With regards to relative font sizes, I would recommend staying
away from em units (the WAI recommends using them:

Due to a bug in IE/PC, they can cause more accessibility
problems than they solve, from my experiences.

IE/PC appears to install with its font size setting to "smaller" or
"smallest" in some cases. If you use an em value less than about
0.95em, your copy will be unreadable by folks who have IE set to
"smaller" by default.

A setting of "medium" by default is the norm, but a noticeable
number of folks do seem to have installs that set themselves to
smaller or smallest by default, and from my experiences the
majority of users out there do _not_ know either that they can
change their browser's font size setting or how they can change it.

Therefore, you have a scenario whereby many users will simply
leave your site in disgust, finding it unreadable. I know because
this is exactly what happened when a site that I had been working
on was launched a few months ago.

The issue with em sizes and IE/PC seems to be that the
"gradiations of change" between smallest, smaller, medium, etc
font size settings are very large when em sizes are employed.
Percentage based font sizes do not seem to suffer the same
rendering issues. Alternatively, simply do not define font sizes at

In terms of using pixels, most new releases of major browsers do
let you resize pixel based font sizes, IE/PC being the major


Leo Smith
Web Designer/Developer
USM Office of Publications and Marketing
University of Southern Maine

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