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
Years to payoff
6.8
Interest saved by paying extra
$4,746.60
Total interest paid
$9,031.28
Monthly payment
$581.48
Months shaved off
39
Total months
81
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter loan balance ($).
- 2Enter interest rate (%).
- 3Enter standard term (years).
- 4Enter extra monthly payment ($).
- 5Read your years to payoff on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Every extra dollar on a student loan goes straight to principal after accrued interest is covered, which is why even $100 a month can cut years off a standard 10-year term.
Worked example
Using the values the calculator loads with:
Inputs
- Loan balance: 38000 $
- Interest rate: 6.5 %
- Standard term: 10 years
- Extra monthly payment: 150 $
Results
- Years to payoff: 6.8
- Interest saved by paying extra: $4,746.60
- Total interest paid: $9,031.28
- Monthly payment: $581.48
- Months shaved off: 39
- Total months: 81
What each field means
Inputs
- Loan balance ($)
- The loan balance used in the calculation, measured in $. Starts at 38000 $ so you have a working example on load.
- Interest rate (%)
- The interest rate used in the calculation, measured in %. Starts at 6.5 % so you have a working example on load. Accepted range: 0–20 %.
- Standard term (years)
- The standard term used in the calculation, measured in years. Starts at 10 years so you have a working example on load. Accepted range: 1–30 years.
- Extra monthly payment ($)
- The extra monthly payment used in the calculation, measured in $. Starts at 150 $ so you have a working example on load.
Results
- Years to payoff
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Interest saved by paying extra
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total interest paid
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- 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.
- Months shaved off
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total months
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the student loan payoff calculator work?
Every extra dollar on a student loan goes straight to principal after accrued interest is covered, which is why even $100 a month can cut years off a standard 10-year term. The underlying maths is: Amortize the balance at the monthly rate, applying any extra payment to principal.
What do I need to enter?
4 values: loan balance, interest rate, standard term, and extra monthly payment. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the years to payoff result mean?
It is returned as a decimal number 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). Student Loan Payoff Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/student-loan-payoff
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/student-loan-payoff" target="_blank" rel="noopener">Student Loan Payoff Calculator — RevenueLab</a> (2026).</p>
Source: [Student Loan Payoff Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/student-loan-payoff) (2026).