There are lots of Free Tools that you can use for your savings and budgeting requirements. What I and my wife is using is the Google Sheets. Through Google Sheet, I can share my calculations with my wife or to whom I wish to share my calculations, The good thing is that Google sheet is Free and calculation in real-time. Whenever any of the users change any information, it will be reflected immediately to the other user as long as they are both online.
Security features are also high, it could not be shared as long as the settings are correct. It can also be shared with specific personnel among your group or within the family. Each member should have their own Gmail account for security purpose.
This also works on the mobile phone, so it is really convenient to use. The formula is also based on excel calculation so a simple arithmetic calculation can be made without any problem.
If you have any other ideas or tools about Free Tools for Savings and Budget Monitoring Please let us know in the comment.