AdOnion
15 websites

AdOnion offers both free and paid options

http://www.adonion.com

Summary AdOnion is the new generation of transparent advertising marketplace to help all the clients both advertisers and publishers to make the most out of both worlds. With new features, we are bringing on a truly transparent marketplace...

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Open AdExchange
8 websites

Open AdExchange is free to use

http://www.openadex.com/

New Danish website is now live: openadexchange.dk ... Targeted ads from Open AdExchange will provide you with additional earnings on top of your existing ...

Market Share by Top Websites

2 In terms of market share, AdOnion is clearly lagging behind, losing to Open AdExchange in all segments.

Websites Categories

1 AdOnion has better usage coverage in more websites categories. Including Arts & Entertainment, Computers Electronics & Technology and Adult.

2 Open AdExchange is leading in Finance, Home & Garden and Jobs & Career.

Geography

1 AdOnion is leading in most countries, including United States, Argentina, Canada, Hong Kong and 6 other countries.

2 Open AdExchange is leading in Denmark, Pakistan and Sweden.