Large zip files may be cumbersome to transport over the internet therefore working with smaller sub-sets of these zips may be easier to manage.  We recommend one of the following methods to either create a multipart zip directly, or split up an existing multi-part zip.

Creating a multi-part ZIP file directly


Creating a multi-part zip using WinRAR

WinRAR is a great tool that can be used for free to zip files on Windows. It also easily allows you to make multi-part zips. Once you've installed WinRAR:

  1. Select the files and folders you wish to zip in Explorer.
  2. Right-click on them.
  3. Click on "Add to archive..." 
  4. Select the "ZIP" format.
  5. Enter a size in the "Split into volumes, size" box and select a unit.

For example below, setting the volume size to "500 MB" while zipping a file that's getting compressed to 2 GB will break it into files named GoldFynch.z01, GoldFynch.z02, GoldFynch.z03, and GoldFynch.z04 each of 500 MB, as well as an additional file named When you're uploading the file to GoldFynch, upload all 5 files.


To create a multi-part zip file on Mac, first create a zip file following these steps, then split it using the method described in the last section of this article.

  1. Select the files you wish to zip in Finder
  2. Right-click on the files
  3. Click on "Compress" - a new file named "" will be created

Splitting an Existing Zip file

Windows - using 7-zip

  1. Download 7-zip.  Click here to download 7-zip.
  2. Install 7-zip.  
  3. Browse to the zip file you wish to split, then right-click the file.
  4. Click the Add button to add to archive.
  5. Click the "split to volumes, bytes" dropdown.
  6. Select the volume option. 
  7. Select OK.
  8. You will now see the separate zip files in the same directory as the original zip file with extensions .z01, .z02, etc, as well as a .zip file. All of these need to be uploaded to GoldFynch.

Mac OSX - Using a command line

  1. Open the Terminal application located in the Other app group in LaunchPad.
  2. Use the "cd" command (change directory) to change the directory.  For example, if your zip folder you need to split resides under Documents, then the command line would be cd Documents
    • NOTE – if your folder contains a space within the folder name, you would replace the space with a “\“  e.g., if your folder is named “Client Folder” the command to change to this location would be cd Client\Folder
  3. Use the command line below to split your zip file into separate zip file segments of 100MB each.
    • E.g. zip  --out -s 100m
    • The result will be: SPLITCLIENTFILES.z01, SPLITCLIENTFILES.z02, SPLITCLIENTFILES.z03 etc. as well as an additional (smaller) file, all of which need to be uploaded to GoldFynch

Click here for a more detailed guide to splitting zip files on Mac OSX.