Text eligibility testing

During the development of the new web site for a client, my company arranged small user testing on text size and fonts. We aimed to find out what font family + size + line-height combination is the favourite among average users.
Since client is a bookie, they have a fairly large amount of phone operators which are sort of ideal testers for this kind of stuff.

Competitors were (all tests were run on Windows platform):

1. Tahoma + 11px font-size + 120% line-height
2. Tahoma + 12px font-size + 100% line-height
3. Verdana + 11px font-size + 100% line-height

Survey of 19 of their office staff resulted in:

• 4 picked (1)
• 6 picked (2)
• 9 picked (3)

Every person surveyed that wore glasses opted for the option (3). This was the decisive factor – web site will use this setting for static content (text boxes at the bottom).
Although the number of people is not that big, it still shows that when you have to use small fonts, Verdana simply rules. Problem are users that don’t have it when Verdana’s overall biginess can backslap you; here it’s a minor problem, since log analysis shows that 99% of users are Win/IE5+ users.
Verdana is also rendered well on Mac OSX.