Loan Payoff Calculator

Find out how many months it will take to pay off a loan given the balance, interest rate, and monthly payment. Free, instant, no signup.

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Formula: months = −log(1 − P×r/M) / log(1+r)
  • P = loan balance
  • r = monthly interest rate
  • M = monthly payment

How to use the Loan Payoff Calculator

  1. Enter your values. Fill in the fields with your numbers.
  2. Calculate. Press Calculate to run the loan payoff calculator.
  3. Use the result. Copy the result or try a related tool next.

Why use our Loan Payoff Calculator

Instant results. Enter your figures and the loan payoff calculator returns an answer in seconds.
Free & private. Runs in your browser — no signup, and nothing is sent to a server.
Accurate. Uses standard formulas so you can rely on the numbers.

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About the Loan Payoff Calculator

The Loan Payoff Calculator shows you how quickly you can clear a loan and how much interest you will avoid by paying more than the minimum each month. You enter your current balance, the annual interest rate, and either your scheduled monthly payment or remaining term, then add an optional extra amount. The tool reports your payoff date, the months you shave off, and the total interest saved. It works for any fixed-rate installment loan, including auto loans, personal loans, student loans, and mortgages, so you can compare what one tweak to your payment really does over the life of the debt.

Reach for this calculator when you have spare cash and want to know whether sending it to a loan beats leaving it idle. It answers concrete questions: if I pay $100 extra a month, when am I debt-free, and how many dollars of interest disappear? Because every extra dollar goes straight to principal, the return is effectively guaranteed at your loan's interest rate, which often beats a savings account. It is also useful before a windfall, a raise, or refinancing, letting you test a one-time lump sum or a permanently higher payment without committing to anything first.

Under the hood the tool runs a month-by-month amortization. Each period it charges interest equal to the remaining balance times the monthly rate (annual rate divided by 12), subtracts that from your payment to find how much principal you retire, and rolls the balance forward. Adding an extra amount shrinks the balance faster, so the next month's interest charge is smaller, which compounds the acceleration. It repeats this loop until the balance hits zero, then compares the accelerated schedule against your original one to report time and interest saved. Results assume a fixed rate and that extra money is applied to principal.

All math runs in your browser, so your balance, rate, and payment figures are never uploaded or stored on our servers. The numbers are accurate for standard fixed-rate, monthly-compounding loans, but treat them as a close estimate rather than a payoff quote. Real loans can differ because of prepayment penalties, daily interest accrual, escrow on mortgages, or a lender applying extra funds to the next payment instead of principal. Always confirm your exact payoff amount with your lender and tell them to direct extra payments to principal.

Frequently asked questions

How does paying extra each month save me interest?

Interest is charged on your remaining balance, so any extra payment applied to principal lowers that balance immediately. A smaller balance means a smaller interest charge the following month, which compounds over time and lets you finish the loan sooner with less total interest.

What inputs do I need to use the calculator?

You need your current loan balance, the annual interest rate (APR), and either your monthly payment or remaining term. Then enter an optional extra monthly amount or one-time lump sum to see the payoff date, months saved, and interest saved.

Will I be charged a fee for paying off my loan early?

Some lenders charge a prepayment penalty, especially on certain mortgages and personal loans. This calculator does not assume a penalty, so check your loan agreement and subtract any fee from the projected interest savings to see your true benefit.

Does the calculator work for mortgages, auto loans, and student loans?

Yes. It works for any fixed-rate installment loan that compounds monthly, including mortgages, auto loans, personal loans, and many student loans. Results may vary slightly for loans that accrue interest daily or include escrow.

How do I make sure my extra payment actually reduces the balance?

Tell your lender to apply the extra amount to principal. Otherwise some lenders treat it as an advance on your next scheduled payment, which does not shorten the term or cut interest the way this calculator assumes.

From our blog

What Do I Need on the Final? A Student's Guide to the Final Grade Calculator

By the Super Simple Digital Tools Team · Updated June 2026

Finals week has a way of making grades feel like a black box, but the math behind them is simpler than it looks. Your course grade is a weighted average: each component test, the final counts for a set share of the total. The final exam is special only because it is usually the last and largest single piece, which means it has the most power to move your grade up or down. Understanding that one fact is the key to using a final grade calculator well, because the tool is really just solving the weighted-average equation in reverse.

To get a useful answer you need three honest inputs. First, your current grade the real, already-weighted number in your gradebook, not your gut feeling or your best test. Second, the weight of the final, which your syllabus states as a percentage of the total. Third, the grade you are targeting, whether that is the cutoff for an A, the line for passing, or simply keeping a scholarship GPA. Feed those in and the calculator returns the exact score you must earn on the exam. If any input is a guess, treat the output as a rough sketch rather than a promise.

A quick worked example makes it concrete. Suppose you are sitting at 75%, the final is worth 40% of the grade, and you want to finish at 80%. The 60% of your grade that is already locked in contributes 0.6 x 75 = 45 points toward the total. You still need 80 - 45 = 35 points to come from the final, and since the final is worth 40 points, you divide: 35 / 0.40 = 87.5%. So an 87.5% on the exam lands you exactly at your 80% goal. Change any input and the required score shifts, which is why it pays to run a few scenarios.

The most valuable thing the calculator does is reveal what is and is not possible. Run your A target and your pass-safe target side by side. If the A requires 96% but a comfortable pass only needs 52%, you instantly know how much risk you are carrying and how hard to push. And if any target demands more than 100%, the tool is telling you the truth early: that goal is off the table without extra credit or a regrade, so it is better to aim at the highest grade you can actually reach than to chase an impossible one.

Use the number as a study plan, not a verdict. A required 88% tells you the exam is winnable but demands real preparation; a required 60% means you can protect your grade by reviewing fundamentals rather than mastering everything. Because the whole calculation happens privately in your browser, you can revisit it as your situation changes after a last-minute quiz score posts, or when you want to compare classes and decide where your limited study hours will do the most good.

  • Always pull your current grade from the gradebook with all weights applied not your latest single test which can be much higher or lower than your real standing.
  • Run two targets at once, like the A cutoff and the passing line, so you can see your best-case stretch goal and your safe floor in the same glance.
  • If the required score comes back above 100%, switch strategies immediately: ask about extra credit or set a reachable target instead of studying toward an impossible number.
  • Double-check the final's weight against your syllabus before trusting the result a 30% final versus a 50% final can change the score you need by 15 points or more.

Read the full guide →

Tool by the Super Simple Digital Tools Team. Reviewed by our editorial team. Free to use, no signup required.

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