Open Calais API

Getting Started with Thomson Reuters Open Calais™ API

Here’s how to get started in three easy steps: get an API key, develop or get an application that uses Open Calais API functionality and then get going.

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Getting Started

Check out the Open Calais Demo and read our Documentation to get started.


Get an API Key

Register and we will send your API key to your email address.



Add sentiment scores to Open Calais – with Finch Computing


To learn more – Go to Intelligent Tagging Developers’ Community