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Mortgage Refinance Calculator

Wondering if it makes sense to refinance your mortgage? Check out the refinance calculator below to determine the potential savings (or lack thereof).

Believe it or not, it doesn’t always make sense to a refinance a home loan, even if mortgage interest rates are stellar.

One must consider the cost to refinance, along with the expected tenure (how long you plan to stay) in the property!

Even if you plan on staying put in the home for life, you still must determine if the loan itself is a keeper long term or just for a little while.

Let this calculator do the heavy lifting so you don’t have to. It’s probably better that you do the calculations as opposed to an interested party, who only gets paid when you refinance!

Refinance Calculator

Enter your current loan details and a proposed new rate to see your monthly savings, breakeven point, payment savings over your planned horizon, and lifetime interest impact.

Current Loan

$
yrs
%
yrs
Years left on your current loan (e.g. a 30-yr loan from 5 years ago has 25 left)
$
Auto-estimated from your loan details — override with your actual statement balance.

New / Refinanced Loan

%
Most refinances reset to 30 yrs, but a 15 or 20-yr refi can save more interest
yrs
$
Typically 2-5% of loan balance — your lender can provide a Loan Estimate

Your Plans

yrs
If you sell or refi again before breakeven, it may not be worth it
$
Leave at $0 for a rate-and-term refi
💡 The breakeven point is how many months of savings it takes to recoup your closing costs. If you plan to stay in the loan past that point, refinancing likely makes financial sense on the monthly-payment level — but check the lifetime interest figure too, since resetting to a longer term can cost more overall even with a lower rate and lower monthly payment.

Breakeven Timeline

Now
Savings accumulate
Breakeven point
Your planned horizon

Cost Comparison

Amortization Schedule

Principal & interest only.

Disclaimer: This calculator is for informational and educational purposes only and does not constitute financial, legal, or tax advice. It does not guarantee loan approval, a specific interest rate, or specific underwriting terms. Your current loan balance is auto-estimated from a standard amortization formula using your original loan amount, original term, current rate, and years already paid — override it with your actual statement balance for accuracy, since extra payments, escrow adjustments, or a mismatch between your inputs and your loan’s actual history will cause the estimate to drift from reality. Interest paid over your planned keep horizon is calculated from your current position in the loan’s amortization schedule, not from the beginning, since interest is front-loaded and using month 1 would overstate how much interest your current loan actually has left to charge during that window. Results assume your current loan’s rate and payment remain unchanged if you don’t refinance. Actual closing costs, rates, and terms depend on your lender and creditworthiness. Consult a licensed mortgage professional before making any decision.

How to Use the Refinance Calculator

To start, enter your original loan amount when you first took out your current mortgage, followed by your remaining loan balance (might need to check your loan servicer’s website for that).

Next enter the remaining loan term, current mortgage rate, and original loan term, which are important to determine the potential savings, and the closing costs on the refinance loan.

For example, a 30-year fixed mortgage has an original term of 30 years or 360 months. And if your original mortgage was for $400,000, enter that number, followed by what the outstanding balance is today.

[Searching for a home loan? See your options with dozens of lenders fast.]

Then enter the proposed new interest rate on the refinance, the new loan term, and the estimated closing costs (and if they’re being paid out-of-pocket or rolled into the loan amount).

The section below that details the proposed refinance loan, including how long you plan to keep the new loan (important!) any cash out you’d like to take out on top of your existing loan balance (optional).

If you aren’t paying any mortgage points or closing costs, simply enter 0. This might be the case if it’s a no closing cost refinance where all costs are absorbed via a slightly higher interest rate thanks to a lender credit.

And if you’re simply refinancing your mortgage into another 30-year mortgage, keep the default 30-year setting. If you want to refinance into a shorter-term loan, such as a 15-year fixed, you’d enter 15 years.

I didn’t include any tax bracket and savings rate information because I wanted to keep this calculator somewhat “simple,” even though it’s still pretty robust as is.

It’s important to enter a ballpark figure for how long you plan to keep the property or the home loan itself. Simply put, the less time you keep your lower-rate mortgage, the less the savings will be. After all, the savings grow each month you pay less money on your mortgage payment.

Once calculated, you will see the monthly payment savings and lifetime interest savings (if applicable) via the lower interest rate, along with the break-even period, which is when upfront closing costs are recouped via lower mortgage payments. It’s essentially how long you need to stay in the loan to actually save money.

Note that if you have a 30-year fixed and take out a new 30-year fixed when refinancing, you could actually more interest across the two loans, even if you save on payments. This is because you’ve extended the loan term in the process.

You can also see the full loan amortization schedule for more details on monthly payments and composition of principal and interest on the refinance loan.

Colin Robertson
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