Usablenet is leading in Top 1M Sites.
Usablenet has better usage coverage in more websites categories. Including Shopping, Business & Industry, Clothing, Sports and 26 other categories.
Vertster is leading in Computer & Electronics, People & Society, Computer Hardware, Career & Education and 7 other categories.
Usablenet is leading in most countries, including United States, United Kingdom, Spain, Italy and 10 other countries.
Vertster hasn't got a lead over Usablenet in any country.