Skip to main content

Installing OpenRefine

System requirements

OpenRefine does not require internet access to run its basic functions. Once you download and install it, it runs as a small web server on your own computer, and you access that local web server by using your browser. It only requires an internet connection to import data from the web, reconcile data using a web service, or export data to the web.

OpenRefine requires three things on your computer in order to function:

Compatible operating system

OpenRefine is designed to work with Windows, Mac, and Linux operating systems. Our team releases packages for each.


Java must be installed and configured on your computer to run OpenRefine. The Mac version of OpenRefine includes Java; new in OpenRefine 3.4, there is also a Windows package with Java included.

If you want to install Java yourself, you can install a pre-built Java Runtime Environment (JRE) from Please note that OpenRefine works with Java 11 to Java 17 for OpenRefine 3.7.

If you install and start OpenRefine on a Windows computer without Java, it will automatically open up a browser window to this page.

Compatible browser

OpenRefine works best on browsers based on WebKit, such as:

We are aware of some minor rendering and performance issues on other browsers such as Firefox. We don't support Internet Explorer. If you are having issues running OpenRefine, see the section on Running.

Release versions

OpenRefine always has a latest stable release, as well as some more recent developments available in beta, release candidate, or snapshot releases. If you are installing for the first time, we recommend the latest stable release.

If you wish to use an extension that is only compatible with an earlier version of OpenRefine, and do not require the latest features, you may find that an older stable version is best for you in our list of releases. Look at later releases to see which security vulnerabilities are being fixed, in order to assess your own risk tolerance for using earlier versions. Look for “final release” versions instead of “beta” or “release candidate” versions.

Unstable versions

If you need a recently developed function, and are willing to risk some untested code, you can look at the most recent items in the list and see what changes appeal to you.

“Beta” and “release candidate” versions may both have unreported bugs and are most suitable for people who are willing to help us troubleshoot these versions by creating bug reports.

For the absolute latest development updates, see the snapshot releases. These are created with every commit.

Installing or upgrading

Back up your data

If you are upgrading from an older version of OpenRefine and have projects already on your computer, you should create backups of those projects before you install a new version.

First, locate your workspace directory. Then copy everything you find there and paste it into a folder elsewhere on your computer.

For extra security you can export your existing OpenRefine projects.


Take note of the extensions you have currently installed. They may not be compatible with the upgraded version of OpenRefine. Installations can be installed in two places, so be sure to check both your workspace directory and the existing installation directory.

Install or upgrade OpenRefine

If you are upgrading an existing OpenRefine installation, you can delete the old program files and install the new files into the same space. Do not overwrite the files as some obsolete files may be left over unnecessarily.


If you have extensions installed, do not delete the webapp\extensions folder where you installed them. You may wish to install extensions into the workspace directory instead of the program directory. There is no guarantee that extensions will be forward-compatible with new versions of OpenRefine, and we do not maintain extensions.

Once you have downloaded the .zip file, extract it into a folder where you wish to store program files (such as D:\Program Files\OpenRefine).

You can right-click on openrefine.exe or refine.bat and pin one of those programs to your Start Menu or create shortcuts for easier access.

Set where data is stored

OpenRefine stores data in two places:

  • program files in the program directory, wherever it is you’ve installed it
  • project files in what we call the “workspace directory.”

You can access the workspace directory by:

  • launch OpenRefine and click Open Project in the sidebar
  • At the bottom of the screen, click Browse workspace directory
  • A file-explorer or finder window will open in your workspace

By default its location is:

Depending on your version of Windows, the data is in one of these directories:

  • %appdata%\OpenRefine
  • %localappdata%\OpenRefine
  • C:\Documents and Settings\(user id)\Local Settings\Application Data\OpenRefine
  • C:\Users\(user id)\AppData\Roaming\OpenRefine
  • C:\Users\(user id)\AppData\Local\OpenRefine
  • C:\Users\(user id)\OpenRefine

For older Google Refine releases, replace OpenRefine with Google\Refine.

You can change this by adding this line to the file openrefine.l4j.ini and specifying your desired drive and folder path:


If your folder path has spaces, use neutral quotation marks around it:

-Drefine.data_dir="D:\My Desired Folder"

If the folder does not exist, OpenRefine will create it.


OpenRefine does not currently output an error log, but because the OpenRefine console window is always open (on Linux and Windows) while OpenRefine runs in your browser, you can copy information from the console if an error occurs.

Using a Mac, you can run OpenRefine using the terminal in order to capture errors.

Increasing memory allocation

OpenRefine relies on having computer memory available to it to work effectively. If you are planning to work with large datasets, you may wish to set up OpenRefine to handle it at the outset. By “large” we generally mean one of the following indicators:

By default OpenRefine is set to operate with 1 gigabyte (GB) of memory (1024MB). If you feel that OpenRefine is running slowly, or you are getting “out of memory” errors (for example, java.lang.OutOfMemoryError), you can try allocating more memory.

A good practice is to start with no more than 50% of whatever memory is left over after the estimated usage of your operating system, to leave memory for your browser to run.

All of the settings below use a four-digit number to specify the megabytes (MB) used (actually mebibytes). The default is usually 1024MB, but the new value doesn't need to be a multiple of 1024.

Dealing with large datasets

If your project is big enough to need more than the default amount of memory, consider turning off Parse cell text into numbers, dates, ... on import. It's convenient, but less efficient than explicitly converting any columns that you need as a data type other than the default “string” type.

Using openrefine.exe

If you run openrefine.exe, you will need to edit the openrefine.l4j.ini file found in the program directory and edit the line

# max memory memory heap size

The line “-Xmx1024M” defines the amount of memory available in megabytes. Change the number “1024” - for example, edit the line to “-Xmx2048M” to make 2048MB [2GB] of memory available.

openrefine.exe not running?

Once you increase the memory allocation, you may find that you cannot run openrefine.exe. In this case, your computer needs a 64-bit version of Java (this is different from Java JDK. Look for the “Windows Offline (64-bit)” download on the Downloads page and install that. Your system must also be set to use the 64-bit version of Java by changing the Java configuration.

Using refine.bat

On Windows, OpenRefine can also be run by using the file refine.bat in the program directory. If you start OpenRefine using refine.bat, the memory available to OpenRefine can be specified either through command line options, or through the refine.ini file.

To set the maximum amount of memory on the command line when using refine.bat, cd to the program directory, then type

refine.bat /m 2048m

where “2048” is the maximum amount of MB that you want OpenRefine to use.

To change the default that refine.bat uses, edit the refine.ini line that reads


Note that this file is only read if you use refine.bat, not openrefine.exe.

Installing extensions

Extensions have been created by our contributor community to add functionality or provide convenient shortcuts for common uses of OpenRefine. We list extensions we know about on our extensions page.

Contributing extensions

If you’d like to create or modify an extension, see our developer documentation here. If you’re having a problem, use our extensions page to go to the page of the extension’s project and report the issue there.

Two ways to install extensions

You can install extensions in one of two places:

  • Into your OpenRefine program folder, so they will only be available to that version/installation of OpenRefine (meaning the extension will not run if you upgrade OpenRefine), or
  • Into your workspace, where your projects are stored, so they will be available no matter which version of OpenRefine you’re using.

We provide these options because you may wish to reinstall a given extension manually each time you upgrade OpenRefine, in order to be sure it works properly.

Find the right place to install

If you want to install the extension into the program folder, go to your program directory and then go to webapp\extensions (or create it if not does not exist).

If you want to install the extension into your workspace, you can:

You can also find your workspace on each operating system using these instructions.

Install the extension

Some extensions have their own instructions: make sure you read the documentation before you begin installing.

Some extensions may have multiple versions, to match OpenRefine versions, so be sure to choose the right release for your installation. If you have questions about compatibility or want to request or voice your support for an update, use our downloads page to go to the extension’s page and report the issue there.

Generally, the installation process will be:

  • Download the extension (usually as a zip file from GitHub)
  • Extract the zip contents into the webapp\extensions directory, making sure all the contents go into one folder with the name of the extension
  • Start (or restart) OpenRefine.

To confirm that installation was a success, follow the instructions provided by the extension. Each extension will appear in its own way inside the OpenRefine interface. Make sure you read its documentation to know where the functionality will appear, such as under specific dropdown menus.