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
Total savings from refinancing
$1,160
Monthly payment reduction
$31.19
New monthly payment
$557.50
Current monthly payment
$588.69
Total paid after refinancing
$23,565
Total paid if you keep the loan
$24,725
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter current loan balance ($).
- 2Enter current apr (%).
- 3Enter months remaining.
- 4Enter new apr (%).
- 5Enter new term (months).
- 6Enter refinance fees ($).
- 7Read your total savings from refinancing on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
Auto refinancing is worth checking once your credit improves or rates fall a point or more. Watch the term: a lower payment on a longer term often costs more in total.
Worked example
Using the values the calculator loads with:
Inputs
- Current loan balance: 21000 $
- Current APR: 9.4 %
- Months remaining: 42
- New APR: 6.2 %
- New term (months): 42
- Refinance fees: 150 $
Results
- Total savings from refinancing: $1,160.16
- Monthly payment reduction: $31.19
- New monthly payment: $557.50
- Current monthly payment: $588.69
- Total paid after refinancing: $23,564.83
- Total paid if you keep the loan: $24,724.99
What each field means
Inputs
- Current loan balance ($)
- The current loan balance used in the calculation, measured in $. Starts at 21000 $ so you have a working example on load.
- Current APR (%)
- The current apr used in the calculation, measured in %. Starts at 9.4 % so you have a working example on load.
- Months remaining
- The months remaining used in the calculation. Starts at 42 so you have a working example on load. Accepted range: 1–96.
- New APR (%)
- The new apr used in the calculation, measured in %. Starts at 6.2 % so you have a working example on load.
- New term (months)
- The new term (months) used in the calculation. Starts at 42 so you have a working example on load. Accepted range: 12–96.
- Refinance fees ($)
- The refinance fees used in the calculation, measured in $. Starts at 150 $ so you have a working example on load.
Results
- Total savings from refinancing
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Monthly payment reduction
- Returned as a money amount in US dollars. 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.
- Current 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.
- Total paid after refinancing
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total paid if you keep the loan
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the auto loan refinance calculator work?
Auto refinancing is worth checking once your credit improves or rates fall a point or more. Watch the term: a lower payment on a longer term often costs more in total. The underlying maths is: Savings = (Old payment × months left) − (New payment × new term) − fees.
What do I need to enter?
6 values: current loan balance, current apr, months remaining, new apr, new term (months), and refinance fees. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the total savings from refinancing result mean?
It is returned as a money amount in US dollars and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
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). Auto Refinance Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/car-refinance
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/car-refinance" target="_blank" rel="noopener">Auto Refinance Calculator — RevenueLab</a> (2026).</p>
Source: [Auto Refinance Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/car-refinance) (2026).