Last week I asked readers to help me work out why some people found the fonts on this site too small to read. In some, if not all, of the cases where this happened, Internet Explorer was set with the Text Size (under the View menu) set to Small. This reduced the text to an unreadable level when the CSS specified sizes in ems, but only reduced it slightly when specified as percentages.
This image shows what was happening. The top two samples have IE’s Text Size on Medium, the default. The left hand sample has CSS sizes specified in ems, the right in roughly equivalent percentages.
If the user then changes their brower’s Text Size to Small, we get the lower examples. The ems sample is reduced far more than the percentages sample. Maybe there’s a logical reason in the complicated world of CSS as to why this is, but it doesn’t seem to make sense to me. Anyway, this site’s fonts are now specified with percentages. Thanks for your help!