How to diff Word documents

It’s fairly straightforward to diff or compare different revisions of an Office document on Windows. The approach below applies to Word, Excel, and PowerPoint files, as well as to ones created by Lotus Symphony, OpenOffice.org, or LibreOffice.

  1. Download and install WinMerge. This is a free, open source utility.
  2. Download the xdocdiff plugin. Unzip it somewhere.
  3. Copy xdoc2txt.exe and zlib.dll to C:\Program Files\WinMerge
  4. Copy amb_xdocdiffPlugin.dll to C:\Program Files\WinMerge\MergePlugins
  5. Start WinMerge.
  6. Go to Plugins > List and check [x] Enable plugins.
  7. Go to Plugins and set it to [x] Automatic unpacking
  8. Close or restart WinMerge

You should now be able to select any two documents that you want to compare, right-click on them, and choose WinMerge to get a meaningful comparison of the textual differences between them.

If you are seeing line noise in the comparison, you need to make sure you enable the settings mentioned in steps 6 and 7 above.

Published by

Leons Petrazickis

I’m a full-stack developer at IBM Digital Business Group. I do Ruby, Node, Python, Hadoop, Spark, as well as web scale devops with Docker and Terraform.

My opinions are my own.