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
Result
Lower total cost option
Refinance
Refinance total cost over stay period
$245,610
Keep current loan total cost
$270,410
Total cost difference
$24,800
Breakeven point
23.4
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How to use this
- 1Enter current loan balance ($).
- 2Enter current rate (%).
- 3Enter years remaining on current loan.
- 4Enter new refinance rate (%).
- 5Enter refinance closing costs ($).
- 6Enter years you plan to stay/keep loan.
- 7Read your lower total cost option on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
Refinancing to a lower rate reduces your monthly payment and total interest, but closing costs eat into those savings until you cross the breakeven month. This calculator compares your current mortgage's remaining interest against a new refinanced loan's interest plus closing costs, and tells you exactly how many months of savings it takes to recoup the cost of refinancing.
Worked example
Using the values the calculator loads with:
Inputs
- Current loan balance: 320000 $
- Current rate: 7.25 %
- Years remaining on current loan: 27
- New refinance rate: 6 %
- Refinance closing costs: 6000 $
- Years you plan to stay/keep loan: 10
Results
- Lower total cost option: Refinance
- Refinance total cost over stay period: $245,610
- Keep current loan total cost: $270,410
- Total cost difference: $24,800
- Breakeven point: 23.4
What each field means
Inputs
- Current loan balance ($)
- The current loan balance used in the calculation, measured in $. Starts at 320000 $ so you have a working example on load.
- Current rate (%)
- The current rate used in the calculation, measured in %. Starts at 7.25 % so you have a working example on load. Accepted range: 0–15 %.
- Years remaining on current loan
- The years remaining on current loan used in the calculation. Starts at 27 so you have a working example on load. Accepted range: 1–30.
- New refinance rate (%)
- The new refinance rate used in the calculation, measured in %. Starts at 6 % so you have a working example on load. Accepted range: 0–15 %.
- Refinance closing costs ($)
- The refinance closing costs used in the calculation, measured in $. Starts at 6000 $ so you have a working example on load.
- Years you plan to stay/keep loan
- The years you plan to stay/keep loan used in the calculation. Starts at 10 so you have a working example on load. Accepted range: 1–30.
Results
- Lower total cost option
- Returned as a plain value and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Refinance total cost over stay period
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Keep current loan total cost
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total 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.
- Breakeven point
- Returned as a length of time. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
What breakeven period is considered good?
A breakeven under 24-36 months is generally considered worth it for most homeowners, since most people stay in a home or keep a loan far longer than that.
Does resetting the loan term matter?
Yes — refinancing into a new 30-year term restarts amortization, so even at a lower rate you may pay more total interest if you were already many years into your current loan; consider matching your remaining term.
Should I include rolled-in closing costs?
If you roll closing costs into the loan balance instead of paying cash, add that amount to your new balance and rerun the numbers — it changes both the payment and the breakeven math.
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). Refinance vs Keep Mortgage Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/refinance-vs-keep-mortgage-cost
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/refinance-vs-keep-mortgage-cost" target="_blank" rel="noopener">Refinance vs Keep Mortgage Calculator — RevenueLab</a> (2026).</p>
Source: [Refinance vs Keep Mortgage Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/refinance-vs-keep-mortgage-cost) (2026).