Usablenet is leading in Top 10K Sites, Top 100K Sites and Top 1M Sites.
Usablenet has better usage coverage in more websites categories. Including Business & Industry, Shopping, People & Society, Travel and 48 other categories.
Vertster is leading in Computer & Electronics, Computer Hardware, Jobs & Employment, Computer Security and 3 other categories.
Usablenet is leading in most countries, including United States, United Kingdom, Japan, Spain and 12 other countries.
Vertster hasn't got a lead over Usablenet in any country.