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 51 other categories.
Zimbio is leading in Arts & Entertainment, People & Society, Music & Audio, TV & Video and 30 other categories.
Riddle is leading in most countries, including United States, United Kingdom, France, Germany and 39 other countries.
Zimbio is leading in Russia, Poland, Sweden, Mexico and 12 other countries.