Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Origination, appraisal, title, recording
Result
Months to break even
23
New monthly payment
$1,867
Monthly saving
$283
Lifetime cost difference
-$59,476
Total remaining on current loan
$619,200
Total on new loan incl. costs
$678,676
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One click, a permanent link with your numbers baked in.
Got your number — what next?
Pick one, it takes 20 secondsHow to use this
- 1Enter remaining loan balance ($).
- 2Enter current principal & interest payment ($/mo).
- 3Enter years left on current loan (years).
- 4Enter new interest rate (%).
- 5Enter new loan term (years).
- 6Enter closing costs ($) — Origination, appraisal, title, recording.
- 7Read your months to break even on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
Refinancing trades a lump of closing costs today for a smaller payment tomorrow, so the whole decision reduces to one question: will you still own the loan when the savings have repaid the costs? This calculator computes the new payment at your target rate and term, the monthly saving against your current payment, and the break-even month. It also flags the trap of resetting the clock — dropping from 22 years remaining back to a fresh 30 lowers the payment but can raise lifetime interest even at a lower rate, so the total-interest comparison is shown alongside.
Worked example
Using the values the calculator loads with:
Inputs
- Remaining loan balance: 320000 $
- Current principal & interest payment: 2150 $/mo
- Years left on current loan: 24 years
- New interest rate: 5.75 %
- New loan term: 30 years
- Closing costs: 6400 $
Results
- Months to break even: 23
- New monthly payment: $1,867.43
- Monthly saving: $282.57
- Lifetime cost difference: -$59,475.93
- Total remaining on current loan: $619,200.00
- Total on new loan incl. costs: $678,675.93
What each field means
Inputs
- Remaining loan balance ($)
- The remaining loan balance used in the calculation, measured in $. Starts at 320000 $ so you have a working example on load.
- Current principal & interest payment ($/mo)
- The current principal & interest payment used in the calculation, measured in $/mo. Starts at 2150 $/mo so you have a working example on load.
- Years left on current loan (years)
- The years left on current loan used in the calculation, measured in years. Starts at 24 years so you have a working example on load.
- New interest rate (%)
- The new interest rate used in the calculation, measured in %. Starts at 5.75 % so you have a working example on load.
- New loan term (years)
- The new loan term used in the calculation, measured in years. Starts at 30 years so you have a working example on load.
- Closing costs ($)
- Origination, appraisal, title, recording
Results
- Months to break even
- Returned as a whole number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- New monthly payment
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Monthly saving
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Lifetime cost difference
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total remaining on current loan
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total on new loan incl. costs
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
What break-even period is acceptable?
A common rule is to refinance only if you will hold the loan at least twice the break-even period. Under 24 months is comfortable for most owners; past 48 months the decision depends heavily on whether you actually stay, and the median US homeowner moves or refinances again well before a 30-year term ends.
Why can a lower rate cost more overall?
Because a new 30-year term restarts amortisation. Interest is front-loaded, so resetting the clock means paying another decade of interest-heavy payments. Compare the lifetime figure, and consider matching the new term to the years you have left.
Should I roll closing costs into the loan?
It preserves cash but you finance the fee for the full term, so the true cost is higher than the sticker. If you roll them in, add them to the balance input here to see the honest payment and break-even.
What about a no-closing-cost refinance?
Those trade fees for a higher rate. Run this twice — once with real costs at the lower rate, once with zero costs at the higher rate — and compare the lifetime numbers over the period you expect to keep the loan.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Mortgage Refinance Break-Even Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/refinance-breakeven-months
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/refinance-breakeven-months" target="_blank" rel="noopener">Mortgage Refinance Break-Even Calculator — RevenueLab</a> (2026).</p>
Source: [Mortgage Refinance Break-Even Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/refinance-breakeven-months) (2026).