Formula and calculation method
Monthly savings = old payment − new payment on the same balance and remaining term. Break-even months = closing costs / monthly savings.
Use consistent units for all comparable inputs. The displayed result is rounded; arithmetic is performed with the full available numeric precision. Check your source measurements before relying on the result.
How to use refinance calculator
- Set Principal / amount. The example below uses 100000.
- Set Existing APR (%). The example below uses 8.
- Set Annual interest rate (%). The example below uses 6.
- Set Term (years). The example below uses 10.
- Set Closing costs. The example below uses 3000.
- Select Calculate to update the result. Reset restores the illustrated inputs. Copy, print or download your own result if you need a record.
Worked example
Example inputs
- Principal / amount
- 100000
- Existing APR (%)
- 8
- Annual interest rate (%)
- 6
- Term (years)
- 10
- Closing costs
- 3000
- Old monthly payment
- 1,213.27594355
- New monthly payment
- 1,110.20501942
- Monthly savings
- 103.07092414
- Break-even months
- 29.10617155
- Lifetime savings after costs
- 9,368.51089645
Factors affecting your result
Use consistent units for all comparable inputs. The displayed result is rounded; arithmetic is performed with the full available numeric precision. Check your source measurements before relying on the result.
Changing principal / amount changes the scenario being evaluated. Adjust one input at a time when comparing results, keep a copy of the assumptions, and compare values using the same unit and period. A precise arithmetic result does not make an uncertain assumption precise.
Frequently asked questions
How does the refinance calculator work?
Monthly savings = old payment − new payment on the same balance and remaining term. Break-even months = closing costs / monthly savings.
What inputs does Refinance Calculator need?
Enter principal / amount, existing apr (%), annual interest rate (%), term (years), closing costs. Read the unit labels; percentages are entered as ordinary percentages, not decimal fractions.
How should I interpret the refinance calculator result?
Use consistent units for all comparable inputs. The displayed result is rounded; arithmetic is performed with the full available numeric precision. Check your source measurements before relying on the result.
Are my refinance calculator inputs uploaded?
No. The calculation runs in this browser. Favorites, recent tool names, theme and formatting preferences may be saved locally, but calculation inputs are not sent to a calculation server or stored by this website. Shared links do not include entered values.
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