From Formula Software:
VBA Code Compare allows you to compare and merge any Visual Basic code embedded into a VBA project (macros, sheet code, module code etc.). This tool uses direct access for working with VB modules. Thus, you don't have to export the source code to a file for comparing and import the edited code back.
You can use this tool for comparing two versions of the same module or for working with the source code when several authors change the code simultaneously.
VBA Code Compare allows you to download the source code of two modules, compare them, synchronize (merge) different parts of code, edit the code before and after comparing and save the changes.
Very useful and intuitive side-by-side code comparison. Sadly, there are more things to do but I only used the comparison aspect. Will update ...
This is - supposedly - a beta version, which - supposedly - will stop being free upon release of version 1.0. I just hope the programmers don't let us early users hanging (although there's a free license for beta reviewers...)
I wanted a free download to compare 2 different versions of Excel VBA code and I downloaded this unreviewed program. I had my doubts but it worked flawlessly. I was amazed to find out how much code I had changed without documenting it!