I've been using Typetester for some time as an online alternative to fiddling around with CSS in order to test out font settings.
However, more recently I've come across a couple of alternatives that show promise.

The first is Designer Plaything, which, while a little rough around the edges, provides a useful alternative to Typetester in that you can try out different headline / body copy combinations.
With some more font options and some further development — more customization options, user-defined text, the addition of sub-headings — this could turn into quite a useful tool.
Designer Plaything also provides a brightness and contrast check of your color settings, which is a nice touch.

The second is Font Tester.
It's very customizable and, like Typetester, allows you to compare fonts against each other.
However, it doesn't include the option to compare headings alongside body copy.
It also seems a little bug-prone which precludes me from recommending it wholeheartedly. For example, in Firefox changing the number of columns via the 'View' option causes the example text to disappear.
Posted on: October 8, 2007 | 7 Comments






7 Comments Posted
Will check them out.
I have actually never thought of using something like this before, so thanks
1. Posted by Jermayn Parker on October 09, 2007
Thanks for this cool tool. Making CSS sheets with the right font just got a bit more simple thanks to you..i pass you a cookie!
2. Posted by Adrian on October 15, 2007
Great tool, thanks!
3. Posted by Kamil Bugala on October 25, 2007
Man, I feel like an idiot because I have never used something like this. What a great idea. Of course, I'm not an active designer but do some stuff on the side. This would save me a ton of time.
4. Posted by Tim Wall on October 26, 2007
Here's another tool: CSS Type
5. Posted by Christian Watson on October 26, 2007
Oh, and Em Calculator looks pretty useful too.
6. Posted by Christian Watson on October 29, 2007
Thank you for your article about "Tools to Compare Fonts Online" and the two links to another css texthelper from the commentars, too.
7. Posted by Ralph on October 30, 2007