How it works
The calculator follows two people month by month. The buyer pays the mortgage plus tax, insurance and upkeep; the renter pays rent. Whoever spends less in a month invests the difference, and the renter also invests the money that would have gone into the down payment and buying costs.
At the end of the period the buyer sells: their wealth is the home's value after selling costs, minus the mortgage still owed, plus their investments. The renter's wealth is their investments. The larger figure wins.
Results are very sensitive to home price growth and investment returns, and to how long you stay — buying usually needs several years to recover the costs of getting in and out.