Riddle is leading in Top 10K Sites, Top 100K Sites and Top 1M Sites.
Riddle has better usage coverage in more websites categories. Including Career & Education, Education, Marketing & Advertising, Video Games and 46 other categories.
Zimbio is leading in Arts & Entertainment, People & Society, Music & Audio, Business & Industry and 33 other categories.
Riddle is leading in most countries, including United States, United Kingdom, France, Germany and 28 other countries.
Zimbio is leading in Russia, Poland, Sweden, Canada and 12 other countries.