The Momentum is a free, open-source rent vs buy calculator designed to help you make a more informed decision about one of the biggest financial choices of your life.
Enter your financial situation — income, savings, home price, rent, timeline — and the calculator models three market scenarios (Conservative, Expected, Optimistic) to show you the projected net worth difference between renting and buying over time.
It factors in mortgage payments, property taxes, insurance, maintenance, opportunity cost of your down payment, investment returns, home appreciation, rent growth, PMI, emergency reserves, and more.
Anyone weighing the rent vs buy decision — first-time homebuyers, renters considering a purchase, or homeowners curious whether renting might have been better. It works across multiple currencies (USD, EUR, AUD).
The calculator uses probability-weighted scenario analysis. Rather than giving you a single answer, it shows what happens across a range of market conditions so you can understand the risk and upside of each path.
The AI explanation feature (available on select plans) provides a personalized narrative based on your specific inputs, but the core financial model is entirely deterministic and transparent.
This tool provides estimates based on the assumptions you enter. It is not financial, tax, or legal advice. Actual costs and returns may vary. Always consult a qualified professional before making housing or investment decisions.