Loan Payoff Calculator - Extra Payments, Lump Sum, Bi-Weekly

Payoff Calculator

Updated Aug 14, 2026 By Jehan Wadia

Introduction

This loan payoff calculator shows you when your debt will be gone. Enter your balance, your interest rate, and your monthly payment. In a second, you will see your payoff date, how much interest you will pay, and how much you could save by paying extra.

It works for a mortgage, car loan, personal loan, student loan, or credit card. You can add extra money each month, drop in a one-time lump sum, or pay a bonus once a year. You can also switch to bi-weekly or weekly payments, which sneaks in one extra payment each year and cuts your interest.

Want to be debt-free by a set date? Type in the month and year, and the tool tells you the exact payment you need. You also get a side-by-side scenario table, a rate sensitivity chart, step-by-step math, and a full amortization schedule you can page through.

Small extra payments go straight to your principal. That means less interest and a much shorter loan. Try a few numbers and see what fits your budget.

How to use our Loan Payoff Calculator

Enter your loan balance, interest rate, payment, and any extra payments. The calculator shows your payoff date, total interest, total paid, and how much time and money you save.

Loan Type: Pick Mortgage, Auto, Personal, Student, or Credit Card. This loads sample numbers that fit that kind of debt.

Current Loan Balance: Type the amount you still owe today, or drag the slider. Do not use the original loan amount.

Annual Interest Rate (APR): Enter the rate on your loan, like 6.50. You can also drag the slider. If you are not sure what your true rate is, run the numbers through the APR calculator first.

Current Monthly Payment: Enter what you pay each month for principal and interest only. Leave out taxes, insurance, and HOA fees. The loan payment calculator can help you confirm this figure.

Remaining Loan Term: Enter the years and months you have left. Click "Set payment from this term" to fill in the payment that matches that term.

Payment Frequency: Choose monthly, bi-weekly, or weekly. Bi-weekly and weekly plans add one extra payment each year, so you finish sooner.

Extra Monthly Payment: Add any amount you pay on top of your normal payment each month. All of it goes to principal. See the extra payment calculator for a deeper look at this single lever.

One-Time Lump Sum Payment: Enter a single big payment, like a bonus or tax refund.

Lump Sum Applied At (month #): Pick the month the lump sum is paid. Use 0 for right now.

Annual Extra Payment: Enter an amount you pay once every 12 months.

Scenario B and Scenario C: Turn these on to test two more plans. Set a different extra payment, lump sum, lump sum month, and annual extra for each. They use the same balance, rate, and payment as your plan.

Target Month and Target Year: Pick the date you want to be debt-free. The calculator solves for the monthly payment you need to hit it.

Click Calculate to see your results, charts, and full amortization schedule. Click Reset to start over.

Paying Off a Loan Early: How It Works

Every loan payment you make is split into two parts. One part covers interest, which is the fee the lender charges you. The other part goes to principal, which is the money you actually borrowed. Only the principal part shrinks your debt. The loan interest calculator breaks that split down payment by payment.

Interest is charged on whatever balance is left. So when you knock the principal down faster, there is less balance to charge interest on. That means every future payment does more work, and the loan ends sooner. This is why a small extra payment can save a large amount of money over time.

Ways to Pay Off Debt Faster

Extra monthly payment: Add a set amount to each payment. All of it goes straight to principal.
Lump sum payment: Put a big one-time amount, like a bonus or tax refund, against the balance. The earlier you do it, the more interest you skip.
Annual extra payment: Pay one extra chunk once a year. Easy to plan around a bonus or gift.
Bi-weekly payments: Pay half your monthly amount every two weeks. There are 26 two-week periods in a year, so you end up making the equal of 13 monthly payments instead of 12. That extra payment goes to principal.
Attack debts in order: With several balances, try the debt snowball (smallest balance first) or the debt avalanche (highest rate first) method.

Why the Interest Rate Matters So Much

A higher APR (annual percentage rate) means more of each payment is eaten by interest. On a high-rate debt like a credit card, most of a small payment can go to interest, and the balance barely moves. The credit card interest calculator and the minimum payment calculator show just how slowly that balance falls. On a low-rate loan, more of each payment goes to principal from the start. This is why many people pay off their highest-rate debt first, or look at a balance transfer or debt consolidation to cut the rate.

What Different Loans Look Like

Mortgages run 15 to 30 years, so even $100 extra a month can cut years off the loan and save thousands in interest — the mortgage payoff calculator and early mortgage payoff calculator focus on that case, and a refinance or recast may be worth comparing. Auto loans and personal loans are shorter, usually 3 to 7 years, so extra payments shorten the term quickly; see the auto loan payoff calculator for vehicle notes. Student loans often have long terms and many separate balances. Credit cards have the highest rates, and paying only the minimum can keep you in debt for decades.

Before You Send Extra Money

Ask your lender to apply extra money to principal, not to next month's payment.
Check for a prepayment penalty. Most loans do not have one, but some do.
Your mortgage payment may include taxes, insurance, and HOA fees. Those are not part of the loan itself, so leave them out when you look at principal and interest. The PITI calculator covers the full housing payment.
Keep an emergency fund first. Money paid into a loan is hard to get back.
Check how the payoff fits your wider picture with a budget calculator or a debt-to-income calculator.

Reading an Amortization Schedule

An amortization schedule lists every payment on the loan. It shows the date, how much goes to interest, how much goes to principal, and the balance that is left. Early on, most of the payment is interest. Later, most of it is principal. Extra payments push that crossover point much closer to today. For a month-by-month table on a home loan, use the mortgage amortization calculator.

Formulas used

Periodic interest rate from APR

i = \frac{\text{APR}\%/100}{m}

Payment per period (base plus extra, split by frequency)

P = \frac{\text{MonthlyPayment}}{d} + \frac{\text{ExtraMonthly}}{d}, \quad d = \frac{m}{12}

Interest charged in period t

I_t = B_{t-1} \cdot i

Principal retired and balance recursion

B_t = B_{t-1} - \left( P + E_t + L_t - I_t \right)

Level payment that amortizes a balance over n months

\text{Pmt} = \frac{B \cdot r}{1 - (1 + r)^{-n}}, \quad r = \frac{\text{APR}\%/100}{12}

Payoff time in months from number of periods

\text{Months} = \frac{N \times 12}{m}

Totals and savings versus the original schedule

\text{TotalPaid} = B_0 + \sum_t I_t, \quad \text{InterestSaved} = \sum_t I_t^{\text{orig}} - \sum_t I_t^{\text{plan}}

Required payment for target date (bisection solve)

\text{Pmt}^{*} = \min \{ P : \text{Months}(P) \le \text{TargetMonths} \}

Frequently asked questions

How accurate is this loan payoff calculator?

The math is exact for a fixed-rate loan. It charges interest on your balance each period, then applies your payment. Your real payoff date may shift by a few days because lenders count actual days between payments and post payments on different dates. Fees, late charges, and rate changes are not included.

Why does my lender show a different payoff amount?

A lender payoff quote adds interest up to the exact day you pay, plus any fees. This tool uses clean monthly periods. Small gaps of a few dollars are normal. Always call your lender for the exact payoff figure before you send a final payment.

What does "month 0" mean for the lump sum?

Month 0 means you pay the lump sum today, before any interest is charged. Month 12 means you pay it one year from now. Earlier is always better, because the money starts cutting interest right away.

What does the "Set payment from this term" button do?

It fills in the payment that would pay off your balance in exactly the years and months you typed. Use it if you know your term but are not sure of your principal and interest payment.

Why does the calculator say my loan will never be paid off?

Your payment is smaller than the interest that builds up each month. The balance grows instead of shrinking. Raise your payment above the monthly interest shown in the warning, and the loan will start to fall.

Why do the "Interest Saved" boxes say to add an extra payment?

Savings are measured against your original monthly schedule. With no extra money and monthly payments, your plan is the same as the original, so there is nothing to save yet. Add an extra amount, a lump sum, or switch to bi-weekly to see numbers there.

What is the interest rate sensitivity table for?

It shows your total interest and payoff time if your rate were 0.5% or 1% higher or lower. Use it to see if a refinance is worth it. If a lower rate saves a lot, compare that saving to the closing costs.

How are Scenario B and Scenario C different from my plan?

They use the same balance, rate, payment, and frequency as your plan. Only the extra payments change. That lets you test two other ideas side by side, like "$400 a month" versus "a $15,000 lump sum next year."

Why can't the calculator hit my target payoff date?

The date is too soon. Even paying the full balance right away could not beat it. Pick a later month or year, or add a bigger lump sum, and the required payment will appear.

Does the required payment include my extra payment?

Yes. The "Required Total Monthly Payment" is the full amount you send each month. The second box shows how much more that is than what you pay now.

Should I include taxes and insurance in my monthly payment?

No. Enter principal and interest only. Escrow money for property taxes, homeowners insurance, PMI, and HOA dues never touches your loan balance, so adding it would make your payoff date look too early.

Does this work for credit cards with minimum payments?

It works if you pay a fixed amount every month. Card minimums shrink as the balance falls, which drags payoff out for years. Pick a set payment you can keep up, and the tool will show how fast the card clears.

Is my information saved or sent anywhere?

No. Everything runs in your browser. Nothing you type is stored or shared. Close the page and the numbers are gone.

Can I use this for a variable or adjustable rate loan?

Only as an estimate. The tool assumes one fixed rate for the whole loan. For an adjustable rate, run it at your current rate, then run it again at a higher rate to see the worst case.

What happens to my regular payment when I pay extra?

Nothing. Your required payment stays the same. The extra money just cuts the balance faster, so you finish early. If you want a lower required payment instead, ask your lender about a recast.

Is it better to pay extra each month or save one big lump sum?

Extra money each month usually wins, because it starts cutting interest right away. A lump sum works well too if you get it early. Test both with Scenario B and C and compare the interest saved.

What are the milestones in the amortization table?

They mark useful points: when your principal payment first beats your interest payment, when you hit 25%, 50%, and 75% paid off, when a lump sum lands, and your final year. Rows with extra money are shaded and tagged.

Why does bi-weekly pay off my loan faster?

You pay half your monthly amount every two weeks. There are 26 of those periods a year, which equals 13 monthly payments instead of 12. That whole extra payment goes to principal every year.

How far ahead can the calculator project?

Up to 60 years. If the balance is still not zero by then, the tool reports that the loan is never paid off at that payment level.

Should I pay off my loan early or invest the money?

Compare the numbers. Paying off a loan gives you a guaranteed return equal to your interest rate. High-rate debt like credit cards is almost always worth clearing first. For a low-rate mortgage, investing may earn more, but it is not guaranteed. Keep an emergency fund either way.