> For the complete documentation index, see [llms.txt](https://docs.simplespa.net/simplespa-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.simplespa.net/simplespa-documentation/fundamentals/pos/common-checkouts-and-tutorial-walkthroughs/applying-notes-and-change-calculator.md).
# Applying Notes & Change Calculator
## Receipt Notes
Notes can be easily added to a transaction receipt by pressing the discrete notes button, this will expand an area to write out any notes to save with the receipt
## Change Calculator
Pressing the calculator button will expand an area to enter the paper bill that has been provided, this will calculate the change that should be returned to the client
I.e. this will simulate an $100 bill given and the change that needs to be returned for a $78 total, the value shown here of $22 is not saved and is only for reference
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