Mortgage Refinance Calculator

Compare current and new mortgage payments.

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Estimate refinance savings

Refinancing can lower a mortgage payment, but closing costs and the remaining term matter. Enter the current balance, current rate, new rate, years remaining and closing costs to estimate the new payment, monthly savings, break-even point and interest savings after costs. It is useful for quick refinance screening before doing a full lender quote.

Break-even view

The break-even estimate divides closing costs by monthly payment savings. If savings are small or negative, a refinance may not pay back the upfront cost.

Method and checks

What the refinance estimate includes

The calculator compares fixed-rate principal-and-interest payments over the same remaining term and treats closing costs as part of the decision.

Method

Each payment uses the standard fixed-payment amortization formula. Break-even months are closing costs divided by estimated monthly savings.

payment = principal x r / (1 - (1 + r)^(-months))

Worked example

For a $300,000 balance with 30 years remaining, 6.5% is about $1,896.20 per month and 5.75% is about $1,750.72. With $6,000 in costs, the simple break-even is about 41.2 months.

Limits

  • The result excludes taxes, insurance, mortgage insurance, escrow changes, and lender-specific fees unless you include them in closing costs.
  • A lower payment can come from restarting or extending the term, which may increase total interest.
  • This is a planning estimate, not a loan offer, APR disclosure, or financial advice.
References

Reviewed against the current calculator or processor on September 6, 2026.

Frequently asked questions

Does this replace a lender quote?

No. It is a planning estimate only.

What term does it use?

The calculator keeps the years remaining the same for both the current and new loan.

Are closing costs included?

Yes. Closing costs are included in the savings comparison.