BYTETOOLS

Mortgage Refinance Calculator

Compare your current mortgage with a refinance offer: new payment, monthly saving, lifetime saving and the break-even month where savings cover closing costs.

$1,807.02
Current payment
$1,498.88
New payment
$308.14
Monthly saving
Month 17
Break-even

Lifetime comparison

Remaining cost, current loan
$542,106.00
Total cost, refinanced loan
$544,596.80
New balance financed
$250,000.00
Paid at closing
$5,000.00
Lifetime extra cost
$2,490.80

The monthly payment falls but the longer term means you pay more overall. Compare a shorter new term before deciding.

Compares principal and interest only — taxes, insurance and escrow are unchanged by a refinance and are left out. Assumes both loans are fixed rate and run to term. Estimates only, not financial advice.

What is the Mortgage Refinance Calculator?

The ByteTools Mortgage Refinance Calculator answers the question that decides most refinances: how long until the savings pay back the closing costs?

  • Amortizes the remaining balance against the proposed rate and term
  • Break-even month where cumulative savings cover closing costs
  • Option to roll closing costs into the new loan or pay up front
  • Compares lifetime cost, not just the monthly payment
  • Warns when a longer new term increases total interest
  • Fully offline; your mortgage details stay on your device

How to use the Mortgage Refinance Calculator

  1. 1

    Enter your current loan balance, interest rate and the months remaining on it.

  2. 2

    Enter the new interest rate and the new term you are being offered.

  3. 3

    Add the closing costs and choose whether to roll them into the new loan.

  4. 4

    Read the monthly saving and the break-even month.

  5. 5

    Check the lifetime cost comparison before deciding.

About the Mortgage Refinance Calculator

The ByteTools Mortgage Refinance Calculator answers the question that decides most refinances: how long until the savings pay back the closing costs? It amortizes your current loan over its remaining term, amortizes the proposed loan at the new rate and term, and compares the two payment streams month by month.

You get the new monthly payment, the monthly saving, the total cost saved or added over the life of the loan, and the break-even month where cumulative savings overtake the cost of refinancing. You can roll the closing costs into the new loan or pay them up front, because that choice changes both the payment and the break-even point.

The tool also flags the trap of restarting the clock: a lower rate over a fresh 30-year term can raise your lifetime interest even while lowering your monthly payment. All calculations run in your browser with nothing uploaded. Estimates only, not financial advice.

Frequently asked questions

When is refinancing worth it?

When you will keep the home long enough to pass the break-even point. If closing costs are $4,000 and refinancing saves $200 a month, you break even after 20 months — so refinancing pays off only if you stay past that.

How is the refinance break-even point calculated?

Divide the total closing costs by the monthly payment saving. This calculator does it month by month instead, accumulating the actual saving each month, which is more accurate when the two loans have different terms.

Can refinancing to a lower rate cost me more?

Yes. If you have 22 years left and refinance into a fresh 30-year loan, you stretch the debt out by eight extra years. The monthly payment falls but the total cost can rise. Compare the lifetime cost figures, not only the payment.

Should I roll closing costs into the loan?

Rolling them in avoids writing a cheque but increases the balance, so you pay interest on the fees for the whole term and the break-even point moves later. Paying up front is cheaper overall if you have the cash available.

What counts as closing costs?

Typically appraisal, origination, title, recording and legal fees, plus any discount points. They commonly run 2% to 5% of the loan amount, though this varies widely by lender and region — enter the figure from your own loan estimate.

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