Klout

The Klout Score measures influence based on your ability to drive action. Every time you create content or engage you influence others. The Klout Score uses data from social networks in order to measure:

• True Reach: How many people you influence
  Your True Reach is the number of people you influence. We filter out spam and bots and focus on the people who are acting on your content. When you post a message, these people tend to respond or share it.
• Amplification: How much you influence them
  Your Amplification is how much you influence people. When you post a message, how many people respond to it or spread it further? If people often act upon your content you have a high Amplification score.
• Network Impact: The influence of your network
  Your Network indicates the influence of the people in your True Reach. How often do top Influencers share and respond to your content? When they do so, they are increasing your Network score.