Understanding your mortgage refinance calculator results
Compare your existing mortgage payment with a possible refinanced rate and estimate when closing costs may pay back. The main result is a starting point for your decision. Review the other figures in the results panel to understand how much of the outcome comes from your inputs and which assumptions have the largest effect.
A change in rate, time horizon or recurring amount can produce a different answer. Try a second scenario before using an estimate in a household or business decision.
How the calculation works
The savings estimate compares fixed-rate installments, while break-even divides closing costs by positive monthly payment difference.
Monthly cash-flow difference = old payment − new payment; break-even months = closing costs ÷ positive monthly difference.
Inputs are validated in your browser, and results use standard mathematical models with the assumptions displayed alongside the output. Depending on the calculator, the chart may show a declining balance, growing savings or a comparison between costs. Read the calculation methodology.
A practical example
A lower APR may reduce the monthly payment, but a longer new term can change lifetime costs.
Use the starting values above to reproduce a scenario, then replace them with your figures. The example is illustrative, not a forecast of rates or market performance.
Important assumptions and limitations
This tool uses numbers you supply and does not fetch personal account information or live lender offers. Interest, inflation, taxes, market returns, lender fees and legal rules vary by product and location. Where a figure is not an actual quote or official rate, treat it as a hypothetical input and verify it independently.
Official resources and further reading
For independent financial context, review a primary source related to this category. Source information may change after this page is published.
Frequently asked questions
How does the mortgage refinance calculator work?
The savings estimate compares fixed-rate installments, while break-even divides closing costs by positive monthly payment difference.
What should I change to compare mortgage refinance calculator scenarios?
Start with remaining loan balance, current apr, current years remaining. A lower APR may reduce the monthly payment, but a longer new term can change lifetime costs. Every output is based on your own inputs.