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Refinance Calculator

Calculate refinance savings, break-even point, and new monthly payment.

⚡ Instant results🔒 Private — runs locally🆓 Free forever🚫 No signup

Refinance Calculator

Calculate refinance savings, break-even point, and new monthly payment.

⚡ Instant🔒 Private🆓 Free🚫 No signupFinancially accurate
$
%
years
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Mortgage Payment Formula

M = P × [r(1+r)ⁿ] ÷ [(1+r)ⁿ – 1]
M = Monthly mortgage payment
P = Principal (loan amount)
r = Monthly interest rate (annual rate ÷ 12)
n = Total payments (years × 12)

ℹ️ Does not include property taxes, homeowner's insurance, or PMI

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Disclaimer

Results provided by this calculator are for informational and educational purposes only. They are based on the values you enter and standard formulas, and should not be considered financial, medical, legal, or professional advice. Always consult a qualified professional before making important decisions based on these results. Roughtools makes no warranties regarding the accuracy or completeness of these calculations for your specific situation.

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Frequently Asked Questions

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Pro Tips

1

Even a 0.5% lower interest rate saves thousands over the life of a loan. Shop at least 3 lenders and get pre-approval before committing — lenders compete on rate when they know you have options.

2

Making one extra payment per year directly toward principal can shorten a 30-year mortgage by 4–6 years and save over $30,000 in interest on a typical home loan.

3

Your Annual Percentage Rate (APR) includes fees the interest rate does not — always compare APR, not just rate, when evaluating lender offers.

4

Bi-weekly payments (half the monthly amount every 2 weeks) result in 26 half-payments per year — equivalent to 13 full monthly payments instead of 12, accelerating payoff.

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When to Use This Calculator

🏠First-time home buyer

Estimate your monthly payment before house hunting to set a realistic budget and avoid over-extending.

🔄Refinancing decision

Compare your current payment to a refinanced rate to calculate the break-even point and total interest savings.

📅Comparing loan terms

15-year vs 30-year mortgage: see the payment difference and total interest cost side-by-side to make an informed choice.

📋Affordability check

Work backwards from your maximum monthly payment to find the home price and loan amount you can comfortably afford.

🏘️Rental property analysis

Calculate the mortgage cost for an investment property to determine if rental income will cover the payment.

About the Refinance Calculator

This refinance calculator compares your current mortgage payment against a new refinanced payment to show your monthly savings, total interest savings, and the break-even point — how long it takes for savings to exceed closing costs. Enter your current loan details and the new rate being offered to make a data-driven refinance decision.

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How to Use the Refinance Calculator

  1. 1

    Enter your current outstanding mortgage balance.

  2. 2

    Enter your current interest rate and remaining term.

  3. 3

    Enter the new interest rate being offered for the refinance.

  4. 4

    Enter the estimated closing costs for the refinance (typically 2–5% of loan).

  5. 5

    See monthly savings, total savings over the loan life, and break-even month.

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