This is the code for a Chrome extension that helps you preview how fonts from the Google Fonts API look on existing webpages. This extension now uses the alpha Google Web Fonts API, so it hopefully auto updates when there are new fonts. The "testing" process is: - Open a webpage, try to apply a font, try to change the style, try to apply a different font, try to reset, try to apply another. - Good webpages are: http://en.wikipedia.org/wiki/Fox (Basics) http://www.mysparebrain.com/svgjs (Tests SVG issue) Here are some features that I would like to add in the future: - Filter font list by serif/sans serif/etc, like on Web Fonts directory - Sort font list (like on Web Fonts directory) If you make improvements to this (like the suggestions above), please let me know.