Marktest is leading in Top 10K Sites and Top 100K Sites.
Vertster has better usage coverage in more websites categories. Including Womens Interests, Internet & Telecom, Computer Hardware, Computer & Electronics and 8 other categories.
Marktest is leading in People & Society, Music & Audio, Arts & Entertainment, News & Media and 3 other categories.
Vertster is leading in most countries, including United States, Australia, Italy and Canada.
Marktest is leading in Brazil.