Riddle is leading in Top 100K Sites and Top 1M Sites.
Riddle has better usage coverage in more websites categories. Including Business & Industry, Career & Education, Education, Internet & Telecom and 54 other categories.
Zimbio is leading in Arts & Entertainment, People & Society, Music & Audio, News & Media and 33 other categories.
Riddle is leading in most countries, including United States, United Kingdom, France, Germany and 38 other countries.
Zimbio is leading in Russia, Sweden, Spain, Poland and 14 other countries.