This is the RefinePro knowledge base about OpenRefine. We build it over the years, and keep adding to it. From great tutorials and how-to, to handy GREL expressions and links to external resources, you will find here one of the most comprehensive list of resources to learn OpenRefine.

For a comprehensive documentation you should refer to the official OpenRefine wiki.

Don't where to get started? Search for a specific function below, or read our most popular article from the right side menu.

29.1.21

OpenRefine January 2021 Review

2021 starts big with the release of the new user documentation for OpenRefine. It took over six months of hard work to migrate the documentation from GitHub wiki to Docusaurus. It was also the opportunity to update the content. 

We also listed below new tutorials and videos published about OpenRefine through January along with the update of the NER and RDF extensions. 



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18.1.21

OpenRefine: Create an empty column

 Sometimes you just need to add a new empty column to your OpenRefine project. The process is straight forward as we show in this video tutorial.


  • From any existing column select the option Edit column and then Add a column based on this column ... 
  • By default, the GREL formula repeat the value from the column you selected
  • Just replace the value with two quotes like this ""  to create an empty string. You can add any text between the quotes. OpenRefine will add it for all the rows selected by your facet.
  • Give your new column and name and click OK
  • and you are done! 
We made a quick video tutorial to show you the steps: 



22.12.20

OpenRefine December 2020 Review

Here is a summary of all the interesting tutorials and videos published about OpenRefine through December. Do not forget to subscribe to our newsletter to get our monthly update right in your mailbox.


30.11.20

OpenRefine November 2020 Review


Here is a summary of all the interesting tutorials and videos published about OpenRefine through November. Do not forget to subscribe to our newsletter to get our monthly update right in your mailbox.

30.10.20

OpenRefine October 2020 Review

Through September and October, the BD Guidance team in Colombia ran numerous workshops on data quality and preparation with OpenRefine (all in Spanish). Fortunately, they recorded everything if you want to catch up. 

Do not forget to subscribe to our newsletter to get our monthly update right in your mailbox.



2.10.20

OpenRefine September 2020 Review

Here is a summary of all the interesting tutorials and videos published about OpenRefine through September. Do not forget to subscribe to our newsletter to get our monthly update right in your mailbox.


17.9.20

Data Operations for CRM and Marketing - OpenRefine Demo - Webinar Recording

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Watch the webinar recording


In case you missed our webinar with Macro on September 10, 2020, you can find here the recording and the slides.

Data management is a core concern facing many companies today. Good data can have a tremendous positive impact on organizational efficiency, productivity, and revenue. Messy data, on the other hand, can have the opposite effect. It can lead to financial losses and disorganization. 


What Is the Business Impact of Data Operations?

  • Better Data-Driven Decisions

  • Improved Lead Management & Qualification

  • Less Frustration


In this webinar, Dan and Martin will discuss the business impact of good data and will touch upon how companies can better manage their data and enhance their data operations strategy.

Martin will also be presenting a demo of OpenRefine, a free open-source data clean up tool.

Dan is the president and founder of Macro. His professional background includes B2B demand generation consulting for Microsoft Dynamics CRM and various international marketing roles in Europe and North America.


Martin is the founder and CEO of RefinePro, a Canadian company focused on data processing and normalization. He created RefinePro to make data within reach of small and medium-sized businesses or departments in larger corporations. Passionate about open source, Martin is a core contributor to the OpenRefine project.


Watch the webinar recording