Klout, a startup that measures influence on Twitter, is releasing a new version of its API today. Klout’s API is currently being used by more than 250 companies, including CoTweet, HootSuite, and the newly-launched Tweetup. You can read our previous coverage of Klout here.

Klout’s API, which is free, can be used by developers to identify the Twitter users they need to connect with to spread word about a new product, by publishers to understand how influential their audience is, and to help marketers and advertisers helping target influencers within your a particular market. The new API now allows users to return a Twitter user’s “True Reach”, “Amplification Score” and “Network nScore” as well as a machine learning classification of the type of user a person is (Connector, Persona). Basically, the API gives third-party users a much richer insight into influencers’ behaviors.

Klout is also adding two new benchmarks to measure authority on its platform. The first, Relationship Method, allows the ability to measure influence between relationships on Twitter. So you can determine who you influence across your social graph or who influences you. The second new feature, Influential Topics, highlights topics where a user is considered influential. These features will also be included in the new version of Klout’s API.

With over 250 clients using Klout’s technologies, it’s clear that the Twitter influence startup is gaining traction, especially in third party Twitter clients. There’s always the risk that Twitter will develop its own measure of authority that can be used, but for now Klout seems to be leading the pack in terms of measuring influence on Twitter.

Crunchbase

• KLOUT

Company: Klout

Website: klout.com

Launch Date: August 2008

Funding: $40M

Klout allows users to track the impact of their opinions, links and recommendations across your social graph. Data is collected about the content users create, how people interact with that content and the size and composition of their networks. Klout identifies influencers and provides tools for influencers to monitor their influence.

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