What platforms does Klout collect social media data from?

At the time of writing - 12th Feb 2018 - Klout lets you connect the following networks to your Klout profile.  It says its Klout score is made up from more than 400 signals from 7 different networks - these are indicated by the listing of metrics against the platform name

Twitter - followers, retweets, mentions, list memberships
Facebook - likes, comments, wall posts, friends
Facebook Page
Blogger
Flickr
Foursquare - tips saved by others, tips liked by others, friends, check-ins, likes, mayorships
Google+ - comments, +1s, reshares (personal profiles only)
Instagram - followers, likes, comments, photographs submitted
Last.fm
Linkedin - connections, recommendations, comments (personal profiles only)
Pinterest
Tumblr
Wordpress.com - inlinks, ratio of inlinks to outlinks, PageRank
Yammer
YouTube

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