Polish Savings calculator
If you invest a fixed amount each month for a number of years this version will calculate how much you will earn in interest. The two buttons at the bottom select the result with and without tax. The Switch toggle shows the period in years or months.
This is set up for a client so their settings may not be the same as yours. But it’s all easily editable of you want something different.
If you want a version like this please contact me.
Note that these plugins are not free. The cost depends on the complexity of the plugin and what changes you need doing.