Ceros is leading in Top 100K Sites and Top 1M Sites.
Ceros has better usage coverage in more websites categories. Including Business & Industry, Arts & Entertainment, Shopping, Marketing & Advertising and 74 other categories.
ReadZ hasn't got a lead over Ceros in any websites category.
Ceros is leading in most countries, including United States, United Kingdom, South Africa, Belgium and 45 other countries.
ReadZ is leading in Ukraine, Bahrain and Kenya.