Riddle is leading in Top 10K Sites, Top 100K Sites and Top 1M Sites.
Riddle has better usage coverage in more websites categories. Including Business & Industry, Career & Education, Education, News & Media and 50 other categories.
Zimbio is leading in Arts & Entertainment, People & Society, Music & Audio, TV & Video and 31 other categories.
Riddle is leading in most countries, including United States, United Kingdom, France, Germany and 35 other countries.
Zimbio is leading in Russia, Spain, Sweden, Poland and 13 other countries.