Return on investment (ROI) is a calculation you can make in order to work out how much money you will be making on an investment. In terms of rental property, this involves balancing the cost of purchase, repairs, taxes and mortgage premiums against rental income. Simply put it is your income divided by your expenses. A simple calculation but with many elements! Our property rental calculator at the top of the page makes things easier. Just input the value of the property you are considering buying (or have bought) along with mortgage repayments and other variables and have the result in seconds. This will show you how to correctly value your rental investment. Good to know For a deep dive, take a look at our guide to rental property investing