In the UK summer emergency budget of July 2015, George Osborne announced that tax relief on mortgage interest payments would be limited to 20% - as opposed to the previous situation, where up to 45% tax relief could be claimed, depending on the rate of tax previously applicable.
Changes were phased in over a period of four years, starting from April 2017.
This website was a quick & dirty calculator to help UK landlords get an idea of what their new tax bill would be.
As of 2021, the new tax regime is in place and anyone who still needs this tool has bigger problems - don't use this code for it's original purpose.
I've put it in a public repo for interest only, and so I don't loose it is my computer dies.
