How can I know with which Microsoft word version a .docx file was saved?

1. Make a copy of the *.docx file and change the extension to *.zip.

2. Open the zip file.

3. Open the docProps\app.xml file.

4. Look at the end for the AppVersion tag value:

   • 12.0000 = Word 2007
   • 14.0000 = Word 2010
   • 15.0000 = Word 2013
   • 16.0000 = Word 2016

I just want to mention that LPChip is 100% wrong. If e.g. you open 2010 created document with 2007 Word, then you will not see any elements/effects because they are not supported. See this list for reference: https://support.office.com/en-us/article/Open-a-Word-2010-document-in-an-earlier-version-of-Word-adfe6ca1-7b18-45a2-ba05-cb1b00ad9935