Celtra is leading in Top 100K Sites and Top 1M Sites.
Celtra has better usage coverage in more websites categories. Including Business & Industry, Computer & Electronics, Sports, Autos & Vehicles and 11 other categories.
SelectMedia is leading in Arts & Entertainment, Career & Education and Education.
Celtra is leading in most countries, including United States, United Kingdom, Canada, China and 19 other countries.
SelectMedia is leading in Israel, Viet Nam and Brazil.