Google Matched Content Publishers
98,454 websites

Google Matched Content Publishers is free to use

https://adsense.googleblog.com/2015/04/introducing-matched-content.html

Provides recommended content advertisements based on page content.

VS

Outbrain Publisher
111,751 websites

Outbrain Publisher offers both free and paid options

http://www.outbrain.com/

Outbrain (www.outbrain.com) is the leading content discovery platform, reaching a highly engaged audience through distribution on top publisher sites, including CNN, Fox News, Hachette Filipacchi Media, Mashable, MSNBC and Slate. Outbrain...

Market Share by Top Websites

1 Outbrain Publisher is leading in Top 10K Sites, Top 100K Sites and The Entire Web.

2 Google Matched Content Publishers is leading in Top 1M Sites.

Websites Categories

1 Outbrain Publisher has better usage coverage in more websites categories. Including Science & Education, Arts & Entertainment, Computers Electronics & Technology, Community & Society and 13 other categories.

2 Google Matched Content Publishers is leading in News & Media, Food & Drink, E-commerce & Shopping, Travel & Tourism and 3 other categories.

Geography

1 Outbrain Publisher is leading in most countries, including United States, France, United Kingdom, Italy and 106 other countries.

2 Google Matched Content Publishers is leading in Japan, South Korea, India, Russia and 47 other countries.