Compare extra monthly mortgage principal payments with investing the same cash flow under a user-entered net return assumption. Use the example values or enter your own numbers to explore an estimate.
Currency formatting only—not an exchange-rate conversion. No country-specific tax or government rules are applied.
Enter your details to see a personalized calculation, a simple projection, and the assumptions behind it.
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The PDF includes active input values and option labels, results, sources, model assumptions, and the schedule when available. Schedule periods follow the model: years, months, or actual payments.
Links include eligible rate, term or frequency assumptions only. Dollar amounts are never included. Recipients must enter their own amounts; the link will not reproduce your full financial scenario.
Convert the quoted nominal annual mortgage rate using the selected compounding convention, and the effective annual investment return to its equivalent monthly rate. Compare the same monthly cash budget. Cap the final loan payment and invest all unused budget after each loan is paid off. Compare investments minus remaining mortgage debt at the selected horizon.
Source/rule review year: Not applicable — general mathematical model.
A nominal annual rate is not the same as an effective annual return. With nominal rate r compounded m times per year, the equivalent effective annual rate is (1 + r / m)m − 1. For example, 6% nominal compounded monthly is about 6.17% effective for a year before fees, taxes, or inflation.
Contribution and withdrawal timing also matters: end-of-month deposits miss that month’s growth, while a beginning-of-period deposit earns for the full period. Compare tools only after matching the rate convention, compounding period, contribution timing, and fees; a displayed equivalent does not make distinct models identical.
Read the compound-interest guide