Beyond Compare - Beyond Compare allows you to compare files and folders.
Microsoft Office Excel - Microsoft Office Excel is a commercial spreadsheet application.
WinMerge - WinMerge is an open source differencing and merging tool for Windows.
Google Sheets - Synchronizing, online-based word processor, part of Google Drive.
Meld - What is Meld? Meld is a visual diff and merge tool targeted at developers.
LibreOffice - Calc - LibreOffice Calc is the spreadsheet program you've always needed. A fork of OpenOffice.