Marktest is leading in Top 10K Sites and Top 100K Sites.
w3roi has better usage coverage in more websites categories. Including Internet & Telecom, Business & Industry, Computer & Electronics, Health and 28 other categories.
Marktest is leading in People & Society, Arts & Entertainment, Music & Audio, News & Media and 2 other categories.
w3roi is leading in most countries, including United States, China, United Kingdom, Canada and 10 other countries.
Marktest is leading in Portugal and Brazil.