How to UnZip a File


Note: The list below is not complete. There are many compression software packages available and most work well. ANES does not endorse any particular software package and cannot be responsible for their use. Some cost money (many have trial periods), and some are free. The links are for your convenience, and take you to third-party websites that are not run by ANES.

  • WinZip
  • 7-Zip
  • StuffIt Expander
  • What is a ZIP file?

    A ZIP file is created to package one or more files into a single file in a compressed format. ZIP files save storage space, are convenient, and can be quicker to download. ZIP files are easy to identify because their filename extension is ".zip".

    ANES datasets are only available for download in ZIP format.

    How do I decompress a ZIP file?

    When you download a ZIP file from a website, you save it to your local computer. You then need to use special software to decompress (unZIP) the file you downloaded. You may already have such software installed; if not, you might want to download one of the software packages shown to the right of this page.

    To decompress the file, you first tell the software where the ZIP file you downloaded is located. The software will then access the files within the ZIP file. Perhaps it will display them to the screen. You then tell the software to decompress (unZIP) the files to a location of your choice. Once this is complete you can begin to use the decompressed files, and you probably will not need to access the ZIP file again.

    Operating System-Specific Help

    The ZIP format was originally intended primarily for use on a PC. However, it is now widely used and can be decompressed on most operating systems.

    There are many options available for decompressing ZIP files on a PC. For those running Microsoft Windows 7 or later, you don't need any extra software. Right click > extract files.

    Decompressing a ZIP file on a Macintosh is also relatively easy to do. Newer Macs have an app called archive utility. Open a Finder window and navigate to the Zip file. Control-click or right-click and select 'compress' from the pop-up menu.

    Some Unix/Linux operating systems already have unZIP software built in; try typing "unzip [filename]" at the command line.

    Many thanks to The Comparative Study of Electoral Systems (CSES) for sharing this help file with us.