Usablenet is leading in Top 100K Sites and Top 1M Sites.
Usablenet has better usage coverage in more websites categories. Including Shopping, Business & Industry, Consumer Electronics, Sports and 32 other categories.
w3roi is leading in Internet & Telecom, Computer & Electronics, Health, Marketing & Advertising and 21 other categories.
Usablenet is leading in most countries, including United States, United Kingdom, Spain, Italy and 7 other countries.
w3roi is leading in China, Taiwan, Philippines, Russia and 4 other countries.