Mortgage Refinance Calculator

Mortgage Refinance Calculator (USA)

Mortgage Refinance Calculator

Find out if switching loans is a smart move—see new payment, break-even, and lifetime interest savings.

Inputs

USA, fixed-rate. Closing costs can be paid upfront or rolled into the new loan.
For both scenarios (current & refi), to compare apples-to-apples
We use standard amortization: Payment = P · r · (1+r)^n / ((1+r)^n − 1)

Results

New monthly payment & savings • Break-even months • Lifetime interest savings
New Monthly Payment
—
Includes rolled closing costs if selected
Monthly Savings
—
vs current payment
You could save — over the life of the loan.
Break-Even Point
—
Months until savings cover closing costs
Total Interest — Current
$0
Remaining life, including any extra principal
Total Interest — Refi
$0
Entire new term, including rolled costs if any
Warning: Your break-even point is longer than your planned time in the home. Refinancing may not pay off unless rates drop further or costs are lower.

What Is Mortgage Refinancing?

Mortgage refinancing means replacing your existing home loan with a new one, usually to get a lower interest rate, reduce monthly payments, or change the loan term. Many homeowners refinance to save money over time or to access equity built in their property.

This mortgage refinance calculator helps you estimate how much you can save by switching to a new loan, including your new monthly payment, break-even point, and long-term interest savings.

How This Mortgage Refinance Calculator Works

This calculator compares your current loan with a new refinance loan based on inputs like remaining balance, interest rate, and loan term.

It calculates:

  • Your new monthly payment
  • Total interest savings
  • Break-even period (when savings cover closing costs)

By adjusting the values, you can quickly see whether refinancing makes financial sense in your situation.

When Is Refinancing a Good Idea?

Refinancing is usually beneficial when:

  • Interest rates are lower than your current rate
  • You want to reduce monthly payments
  • You plan to stay in your home long enough to recover closing costs
  • You want to switch from an adjustable-rate to a fixed-rate mortgage

Always consider fees and how long you plan to stay in the property before refinancing.

How to Use This Mortgage Refinance Calculator

  1. Enter your Current Loan Details: Remaining Balance, Interest Rate (APR %), Remaining Term (years)
  2. Enter your New Loan Details: New Interest Rate (APR %), New Loan Term (years), Closing Costs ($)
  3. Check “Roll closing costs into the new loan” if you want to finance them
  4. Enter Planned Time Remaining in Home (years) — to see if refinance makes sense
  5. Enter Extra Monthly Principal (optional) for both scenarios
  6. Click Calculate — see new monthly payment, monthly savings, break-even period, and lifetime interest savings

How Refinance Savings Are Calculated

Monthly Payment = P × r × (1+r)^n / ((1+r)^n — 1)
Monthly Savings = Current Payment — New Payment
Break-Even (months) = Closing Costs ÷ Monthly Savings
Lifetime Interest Savings = Current Total Interest — Refi Total Interest

Real Example

Current Loan:

  • Remaining Balance: $320,000
  • Current Rate: 6.25%
  • Remaining Term: 25 years

New Loan:

  • New Rate: 5.25%
  • New Term: 30 years
  • Closing Costs: $6,000
  • Roll Closing Costs: No
  • Planned Stay: 7 years

Results:

  • Current Monthly Payment: $2,113
  • New Monthly Payment: $1,767
  • Monthly Savings: $346
  • Break-Even: 17 months (1.4 years)
  • Lifetime Interest Savings: $98,000+
  • Verdict: Refinance makes sense (break-even < planned stay)

Why Use This Mortgage Refinance Calculator?

  • ✅ Full Refinance Analysis — Compare current vs new loan side-by-side
  • ✅ Break-Even Calculation — Know exactly when savings cover closing costs
  • ✅ Lifetime Interest Savings — See total interest saved over loan life
  • ✅ Closing Cost Options — Compare paying upfront vs rolling into loan
  • ✅ Stay Duration Warning — Alerts if break-even exceeds planned stay
  • ✅ Extra Principal Support — Add extra payments to both scenarios
  • ✅ Free & Unlimited — No signup required
  • ✅ Mobile Friendly — Responsive design for phones, tablets, and desktops

Frequently Asked Questions

When does refinancing make sense?

Refinancing is beneficial when:
– Interest rates dropped at least 0.5-1% below your current rate
– Break-even period is less than your planned stay in the home
– You want to lower monthly payments or shorten loan term
– You have good credit (680+ for best rates)

What is break-even period?

Break-even period is the time it takes for your monthly savings to equal your closing costs. If you sell or refinance again before break-even, you lose money on the refinance.

Should I roll closing costs into the loan?

Pros: No upfront cash needed, lower out-of-pocket at closing.
Cons: Increases loan balance, you pay interest on closing costs, and monthly savings are slightly lower.

What are typical refinance closing costs?

Typical refinance closing costs: 2-5% of loan amount ($4,000-$10,000 on $200k loan). Includes:
– Origination/application fees
– Appraisal fee ($400-700)
– Title search and insurance
– Credit report fee
– Recording fees

How much do I need to save to make refinance worth it?

A common rule of thumb: refinance if you can lower your rate by at least 0.5-1% and plan to stay past the break-even point. Run the numbers — this calculator does exactly that.

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Disclaimer: This mortgage refinance calculator provides estimates for informational purposes only. Actual refinance savings vary by lender, credit score, loan type, and market conditions. Consult a mortgage professional before making refinancing decisions.